NilsML/retriever_dataset · Datasets at Hugging Face

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Which trait of particles causes even cold objects to have some thermal energy?	kinetic energy	equilibrium	momentum	constant random motion	Scientists think that multicellularity arose from cooperation between many organisms of the same species. The Colonial Theory proposes that this cooperation led to the development of a multicellular organism. Many examples of cooperation between organisms in nature have been observed. For example, a certain species of amoeba (a single-celled protist) groups together during times of food shortage and forms a colony that moves as one to a new location. Some of these amoebas then become slightly differentiated from each other. Volvox, shown in Figure above , is another example of a colonial organism. Most scientists accept that the Colonial theory explains how multicellular organisms evolved.
Found in many electric devices, what is a coil of wire wrapped around a bar of iron or other ferromagnetic material?	actuator	battery	superconductor	electromagnet	The animal mole is very different than the counting unit of the mole. Chemists nonetheless have adopted the mole as their unofficial mascot. National Mole Day is a celebration of chemistry that occurs on October 23rd (10/23) of each year.
What is it called when two organisms live close together and form a relationship?	Family	definitions	traits	symbiosis	Fungi don't live in isolation. They often interact with other species. In fact, fungi can be dependent on another organism for survival. When two species live close together and form a relationship, it is called symbiosis . Symbiosis can be beneficial to one or both organisms, or sometimes one organism hurts the other. Some of the partners in these relationships include plants, algae, insects and other animals, and even humans.
What does fsh help stimulate in the ovaries and sperm in the testes?	spawning	in vitro fertilization	dna replication	maturation of eggs	Peptide and Protein Hormones Whereas the amine hormones are derived from a single amino acid, peptide and protein hormones consist of multiple amino acids that link to form an amino acid chain. Peptide hormones consist of short chains of amino acids, whereas protein hormones are longer polypeptides. Both types are synthesized like other body proteins: DNA is transcribed into mRNA, which is translated into an amino acid chain. Examples of peptide hormones include antidiuretic hormone (ADH), a pituitary hormone important in fluid balance, and atrial-natriuretic peptide, which is produced by the heart and helps to decrease blood pressure. Some examples of protein hormones include growth hormone, which is produced by the pituitary gland, and follicle-stimulating hormone (FSH), which has an attached carbohydrate group and is thus classified as a glycoprotein. FSH helps stimulate the maturation of eggs in the ovaries and sperm in the testes.
The largest phylum of the animal kingdom is what?	crustaceans	cephalopods	mammals	arthropods	Arthropods are not only the largest phylum of invertebrates. They are by far the largest phylum of the animal kingdom. Roughly 80 percent of all animal species living on Earth today are arthropods. Obviously, arthropods have been extremely successful. What accounts for their success?.
During what process is light from the star focused and the star appears to brighten in a characteristic manner?	macrolensing	spectrometry	excitation	microlensing	In a process called microlensing, light from the star is focused and the star appears to brighten in a characteristic manner. Searches for dark matter in this form are particularly interested in galactic halos because of the huge amount of mass that seems to be there. Such microlensing objects are thus called massive compact halo objects, or MACHOs. To date, a few MACHOs have been observed, but not predominantly in galactic halos, nor in the numbers needed to explain dark matter. MACHOs are among the most conventional of unseen objects proposed to explain dark matter. Others being actively pursued are red dwarfs, which are small dim stars, but too few have been seen so far, even with the Hubble Telescope, to be of significance. Old remnants of stars called white dwarfs are also under consideration, since they contain about a solar mass, but are small as the Earth and may dim to the point that we ordinarily do not observe them. While white dwarfs are known, old dim ones are not. Yet another possibility is the existence of large numbers of smaller than stellar mass black holes left from the Big Bang—here evidence is entirely absent. There is a very real possibility that dark matter is composed of the known neutrinos, which may have small, but finite, masses. As discussed earlier, neutrinos are thought to be massless, but we only have upper limits on their masses, rather than knowing they are exactly zero. So far, these upper limits come from difficult measurements of total energy emitted in the decays and reactions in which neutrinos are involved. There is an amusing possibility of proving that neutrinos have mass in a completely different way. We have noted in Particles, Patterns, and Conservation Laws that there are three flavors of neutrinos ( ν e ,.
Much like the processes of dna replication and transcription, translation consists of three main stages: initiation, elongation, and this?	detonation	isolation	assimilation	termination	Much like the processes of DNA replication and transcription, translation consists of three main stages: initiation, elongation, and termination. Initiation takes place with the binding of a ribosome to an mRNA transcript. The elongation stage involves the recognition of a tRNA anticodon with the next mRNA codon in the sequence. Once the anticodon and codon sequences are bound (remember, they are complementary base pairs), the tRNA presents its amino acid cargo and the growing polypeptide strand is attached to this next amino acid. This attachment takes place with the assistance of various enzymes and requires energy. The tRNA molecule then releases the mRNA strand, the mRNA strand shifts one codon over in the ribosome, and the next appropriate tRNA arrives with its matching anticodon. This process continues until the final codon on the mRNA is reached which provides a “stop” message that signals termination of translation and triggers the release of the complete, newly synthesized protein. Thus, a gene within the DNA molecule is transcribed into mRNA, which is then translated into a protein product (Figure 3.29).
Each hemisphere of the cerebrum consists of four parts, called what?	quarters	rows	layers	lobes	Each hemisphere of the cerebrum consists of four parts, called lobes. Each lobe is associated with particular brain functions. Just one function of each lobe is listed here.
What is an organic compound that is the primary component of natural gas?	sulfur	ethanol	magnesium	methane	Methane is an organic compound that is the primary component of natural gas. Its structure consists of a central carbon atom with four single bonds to hydrogen atoms (see Figure below ). In order to maximize their distance from one another, the four groups of bonding electrons do not lie in the same plane. Instead, each of the hydrogen atoms lies at the corners of a geometrical shape called a tetrahedron. The carbon atom is at the center of the tetrahedron. Each face of a tetrahedron is an equilateral triangle.
What is raising the temperature of earth’s surface?	Coriolis effect	ozone layer	photosynthesis effect	greenhouse effect	Gases such as carbon dioxide from the burning of fossil fuels increase the natural greenhouse effect. This is raising the temperature of Earth’s surface, and is called global warming.
What is a measure of randomness or disorder in a system?	chaos theory	enthropy	biodiversity	entropy	Figure 6.12 Entropy is a measure of randomness or disorder in a system. Gases have higher entropy than liquids, and liquids have higher entropy than solids.
What is the distance between two corresponding points of adjacent waves called?	variation	wave distance	bandwidth	wavelength	Wave amplitude is the maximum distance the particles of a medium move from their resting positions as a wave passes through. Wavelength is the distance between two corresponding points of adjacent waves. Waves with greater amplitudes or shorter wavelengths have more energy.
Crossing-over is the exchange of genetic material between which chromosomes?	analogous	metacentric	monogamous	homologous	When homologous chromosomes form pairs during prophase I of meiosis I, crossing-over can occur. Crossing-over is the exchange of genetic material between homologous chromosomes. It results in new combinations of genes on each chromosome.
What is a ridge of sand that extends away from the shore?	a scoop	a dig	a depression	a spit	A spit is a ridge of sand that extends away from the shore. The end of the spit may hook around toward the quieter waters close to shore.
Manganin is made up of metals that include copper, manganese and nickel - what do you generally call a metal of this type?	mixed metal	complex metal	silicon	alloy	for metals, meaning their resistivity increases with temperature. Some alloys have been developed specifically to have a small temperature dependence. Manganin (which is made of copper, manganese and nickel), for example, has α close to zero (to three digits on the scale in Table 20.2), and so its resistivity varies only slightly with temperature. This is useful for making a temperature-independent resistance standard, for example.
Protons and neutrons are located in which central part of the atom?	radius	shell	nucleolus	nucleus	Electrons have almost no mass. Instead, almost all the mass of an atom is in its protons and neutrons in the nucleus. The nucleus is very small, but it is densely packed with matter. The SI unit for the mass of an atom is the atomic mass unit (amu) . One atomic mass unit equals the mass of a proton, which is about 1.7 × 10 -24 g. Each neutron also has a mass of 1 amu. Therefore, the sum of the protons and neutrons in an atom is about equal to the atom’s total mass in atomic mass units.
Cancer is the result of unchecked cell division caused by a breakdown of the mechanisms that regulate this?	respiration	blood flow	digestion	cell cycle	10.4 Cancer and the Cell Cycle Cancer is the result of unchecked cell division caused by a breakdown of the mechanisms that regulate the cell cycle. The loss of control begins with a change in the DNA sequence of a gene that codes for one of the regulatory molecules. Faulty instructions lead to a protein that does not function as it should. Any disruption of the monitoring system can allow other mistakes to be passed on to the daughter cells. Each successive cell division will give rise to daughter cells with even more accumulated damage. Eventually, all checkpoints become nonfunctional, and rapidly reproducing cells crowd out normal cells, resulting in a tumor or leukemia (blood cancer).
Slabs of continents moving around on earth's surface is called what?	fault tectonics	edge tectonics	crator tectonics	plate tectonics	Plate tectonics theory says that slabs of continents move around on Earth's surface. The mechanism for that movement is seafloor spreading. Plate tectonics explain many things about Earth: (1) geological activity, why it happens where it does; (2) natural resources, why many are found where they are; and (3) the past and future, what happened in the past and what will happen in the future. The theory of plate tectonics will be explored in the chapter Plate Tectonics .
In plants, what structure located above the root cap is where growth in length occurs?	elections meristem	secondary meristem	support meristem	primary meristem	As shown in Figure below , the tip of a root is called the root cap. It consists of specialized cells that help regulate primary growth of the root at the tip. Above the root cap is primary meristem, where growth in length occurs.
With what does an electromagnetic wave start?	battery	kinetic energy	static charged particle	vibrating charged particle	An electromagnetic wave starts with a vibrating charged particle.
What kind of overdose do eudicots die from?	chemical	nutritional	metabolic	hormonal	null
The particles in a colloid are large enough to scatter light, a phenomenon called what?	bowman effect	astral effect	jonah effect	tyndall effect	The particles in a colloid are large enough to scatter light, a phenomenon called the Tyndall effect. This can make colloidal mixtures appear cloudy or opaque, such as the searchlight beams shown in Figure 11.31. Clouds are colloidal mixtures. They are composed of water droplets that are much larger than molecules, but that are small enough that they do not settle out.
What two things limit primary production in aquatic ecosystems?	air and light	air and nutrients	pollution and nutrients	light and nutrients	null
Vascular and non-vascular are two groups of what kind of organism?	fungi	animals	vertebrates	plants	The Major Divisions of Land Plants The green algae and land plants are grouped together into a subphylum called the Streptophytina, and thus are called Streptophytes. In a further division, land plants are classified into two major groups according to the absence or presence of vascular tissue, as detailed in Figure 25.6. Plants that lack vascular tissue, which is formed of specialized cells for the transport of water and nutrients, are referred to as non-vascular plants. Liverworts, mosses, and hornworts are seedless, non-vascular plants that likely appeared early in land plant evolution. Vascular plants developed a network of cells that conduct water and solutes. The first vascular plants appeared in the late Ordovician and were probably similar to lycophytes, which include club mosses (not to be confused with the mosses) and the pterophytes (ferns, horsetails, and whisk ferns). Lycophytes and pterophytes are referred to as seedless vascular plants, because they do not produce seeds. The seed plants, or spermatophytes, form the largest group of all existing plants, and hence dominate the landscape. Seed plants include gymnosperms, most notably conifers (Gymnosperms), which produce “naked seeds,” and the most successful of all plants, the flowering plants (Angiosperms). Angiosperms protect their seeds inside chambers at the center of a flower; the walls of the chamber later develop into a fruit.
The burning of fossil fuels has increased which effect?	ozone effect	natural gas effect	photosynthesis effect	greenhouse effect	The burning of fossil fuels has increased the greenhouse effect and caused global climate change. Increasing temperatures are changing basic climate factors of habitats, and rising sea levels are covering them with water. These changes threaten many species.
What do you call geographical areas that contain high numbers of endemic species?	endospots	warmspots	multispots	hotspots	A simple measure of success in setting aside preserves for biodiversity protection is to set a target percentage of land or marine habitat to protect. However, a more detailed preserve design and choice of location is usually necessary because of the way protected lands are allocated and how biodiversity is distributed: protected lands tend to contain less economically valuable resources rather than being set aside specifically for the species or ecosystems at risk. In 2003, the IUCN World Parks Congress estimated that 11.5 percent of Earth’s land surface was covered by preserves of various kinds. This area is greater than previous goals; however, it only represents 9 out of 14 recognized major biomes and research has shown that 12 percent of all species live outside preserves; these percentages are much higher when threatened species are considered and when only high quality preserves are considered. For example, high quality preserves include only about 50 percent of threatened amphibian species. The conclusion must be that either the percentage of area protected must be increased, the percentage of high quality preserves must be increased, or preserves must be targeted with greater attention to biodiversity protection. Researchers argue that more attention to the latter solution is required. A biodiversity hotspot is a conservation concept developed by Norman Myers in 1988. Hotspots are geographical areas that contain high numbers of endemic species. The purpose of the concept was to identify important locations on the planet.
What type of climate do most agaves grow in?	tropical	arctic	rainforest	arid	null
What cells secrete signaling molecules that promote sperm production and can control whether germ cells live or die?	egg cells	erythrocytes	neurons	sertoli cells	Sertoli Cells Surrounding all stages of the developing sperm cells are elongate, branching Sertoli cells. Sertoli cells are a type of supporting cell called a sustentacular cell, or sustenocyte, that are typically found in epithelial tissue. Sertoli cells secrete signaling molecules that promote sperm production and can control whether germ cells live or die. They extend physically around the germ cells from the peripheral basement membrane of the seminiferous tubules to the lumen. Tight junctions between these sustentacular cells create the blood–testis barrier, which keeps bloodborne substances from reaching the germ cells and, at the same time, keeps surface antigens on developing germ cells from escaping into the bloodstream and prompting an autoimmune response.
Invertebrate chordates use what to filter food out of water?	nose	pores	tails	gills	Invertebrate chordates use their gills to filter food out of water, not to absorb oxygen. In the early evolution of fish, there was a switch to using gills to absorb oxygen instead of to filter food. Gills consist of many thin, folded tissues that provide a large surface area for oxygen uptake. With more oxygen absorbed by the gills, fish could become much larger and more active.
Because the current is alternating, the magnetic field of the iron core keeps doing what?	decreasing	increasing	changing	reversing	The transformer in the diagram consists of two wire coils wrapped around an iron core. Each coil is part of a different circuit. When alternating current passes through coil P, it magnetizes the iron core. Because the current is alternating, the magnetic field of the iron core keeps reversing. This is where electromagnetic induction comes in. The changing magnetic field induces alternating current in coil S of the other circuit.
When heat moves out of a system, what is the sign of the enthalpy?	N/A (zero)	it depends	positive	negative	where H is the enthalpy of the system, E is the internal energy, P is the pressure, and V is the volume. It can be difficult to distinguish "heat" and "enthalpy. " Heat measures the transfer of thermal energy between two objects, and enthalpy measures the flow of heat. When heat flows out of a system, the change in enthalpy is negative; when heat flows into a system, the change in enthalpy is positive. Enthalpy is a useful tool for characterizing chemical reactions.
What occurs when light bumps into tiny particles of matter and spreads out in all directions?	rainbow effect	kaleidoscope	darkness	scattering	Scattering occurs when light bumps into tiny particles of matter and spreads out in all directions. In the Figure below , beams of light from car headlights are shining through fog. The light is scattered by water droplets in the air, giving the headlights a “halo” appearance.
During unfavorable conditions, mature seeds may enter a period of inactivity or extremely low metabolic activity called what?	malignancy	hibernation	germination	dormancy	Seed Germination Many mature seeds enter a period of inactivity, or extremely low metabolic activity: a process known as dormancy, which may last for months, years or even centuries. Dormancy helps keep seeds viable during unfavorable conditions. Upon a return to favorable conditions, seed germination takes place. Favorable conditions could be as diverse as moisture, light, cold, fire, or chemical treatments. After heavy rains, many new seedlings emerge. Forest fires also lead to the emergence of new seedlings. Some seeds require vernalization (cold treatment) before they can germinate. This guarantees that seeds produced by plants in temperate climates will not germinate until the spring. Plants growing in hot climates may have seeds that need a heat treatment in order to germinate, to avoid germination in the hot, dry summers. In many seeds, the presence of a thick seed coat retards the ability to germinate. Scarification, which includes mechanical or chemical processes to soften the seed coat, is often employed before germination. Presoaking in hot water, or passing through an acid environment, such as an animal’s digestive tract, may also be employed. Depending on seed size, the time taken for a seedling to emerge may vary. Species with large seeds have enough food reserves to germinate deep below ground, and still extend their epicotyl all the way to the soil surface. Seeds of smallseeded species usually require light as a germination cue. This ensures the seeds only germinate at or near the soil surface (where the light is greatest). If they were to germinate too far underneath the surface, the developing seedling would not have enough food reserves to reach the sunlight.
Solid coal, liquid petroleum, and liquid natural gas are all types of what?	solar electric	nuclear fusion	hydroelectric	fossil fuels	Fossil fuels include solid coal, liquid petroleum, and liquid natural gas.
What everyday beverage commodity is second only to oil in worldwide trade?	beer	water	soda	coffee	Chemistry in Everyday Life Decaffeinating Coffee Using Supercritical CO2 Coffee is the world’s second most widely traded commodity, following only petroleum. Across the globe, people love coffee’s aroma and taste. Many of us also depend on one component of coffee—caffeine—to help us get going in the morning or stay alert in the afternoon. But late in the day, coffee’s stimulant effect can keep you from sleeping, so you may choose to drink decaffeinated coffee in the evening. Since the early 1900s, many methods have been used to decaffeinate coffee. All have advantages and disadvantages, and all depend on the physical and chemical properties of caffeine. Because caffeine is.
Where are ribosomes made?	protoplasm	cell membrane	mitochondria	the nucleolus	The nucleolus is inside the nucleus, and is where ribosomes are made.
What prevents loss of water from the body and keeps out microorganisms?	sweat	muscles	hydration	the skin'	The skin prevents loss of water from the body and keeps out microorganisms. Melanin in the epidermis protects the dermis from damaging ultraviolet light. By dilating or contracting its blood vessels and releasing sweat, skin helps maintain a constant body temperature.
Batteries containing a liquid electrolyte, like those in cars, are referred to as what kind of battery?	lithium cell	time cell	sand cell	wet cell	The car battery is an example of a “wet cell” battery, because there is a liquid electrolyte (sulfuric acid) present in the system. These batteries must operate in an upright position so the liquid material does not spill out. In contrast, dry cell batteries contain a paste that serves as the positive electrode. The composition and voltage depends on the specific battery, but typical voltage outputs are in the 1.0-1.5 volt range.
Stp, which is important in determining information about gas behavior and properties, stands for standard temperature and what?	push	pull	power	pressure	It should be obvious by now that some physical properties of gases depend strongly on the conditions. What we need is a set of standard conditions so that properties of gases can be properly compared to each other. Standard temperature and pressure (STP) is defined as exactly 100 kPa of pressure (0.986 atm) and 273 K (0°C). For simplicity, we will use 1 atm as standard pressure. Defining STP allows us to compare more directly the properties of gases that differ from each other. One property shared among gases is a molar volume. The molar volume is the volume of 1 mol of a gas. At STP, the molar volume of a gas can be easily determined by using the ideal gas law:.
Within a particular habitat, what can be characterized by its size or density?	percent	total	group	population	Population Size and Density The study of any population usually begins by determining how many individuals of a particular species exist, and how closely associated they are with each other. Within a particular habitat, a population can be characterized by its population size (N), the total number of individuals, and its population density, the number of individuals within a specific area or volume. Population size and density are the two main characteristics used to describe and understand populations. For example, populations with more individuals may be more stable than smaller populations based on their genetic variability, and thus their potential to adapt to the environment. Alternatively, a member of a population with low population density (more spread out in the habitat), might have more difficulty finding a mate to reproduce compared to a population of higher density. As is shown in Figure 45.2, smaller organisms tend to be more densely distributed than larger organisms.
Animals that eat decomposing organic material, such as dung beetles, make the material available to what organisms that break it down further?	protozoa	consumers	pathogens	bacteria	Animals that eat decomposing organic material also have an important interaction with the environment. They help to decompose dead matter and assist with the recycling of nutrients. By burying and eating dung, dung beetles, such as the one shown in Figure below , improve nutrient cycling and soil structure. They make the dead organic matter available to bacteria that break it down even further.
Skin that acts as camouflage or secretes chemicals poisonous to predators are successful modification in frogs and salamanders, classed as what in the order anura?	reptiles	parasites	fungi	amphibians	View River Monsters: Fish With Arms and Hands? (http://openstaxcollege. org/l/river_monster) to see a video about an unusually large salamander species. Anura: Frogs Frogs are amphibians that belong to the order Anura (Figure 29.17). Anurans are among the most diverse groups of vertebrates, with approximately 5,965 species that occur on all of the continents except Antarctica. Anurans have a body plan that is more specialized for movement. Adult frogs use their hind limbs to jump on land. Frogs have a number of modifications that allow them to avoid predators, including skin that acts as camouflage. Many species of frogs and salamanders also release defensive chemicals from glands in the skin that are poisonous to predators.
What do you call people who study science and are experts in one or more fields of science?	doctors	chemists	animals	scientists	Scientists are regular people who chose to study science. They are experts in done or more fields of science.
In budding , organisms reproduce by having new individuals split off from what?	a sister chromatid	ova	nuclei	existing ones	In budding , organisms reproduce by having new individuals split off from existing ones, which results in genetically identical parent and daughter organisms. The bud may stay attached or break free from the parent. Eukaryotic organisms, such as the single cell yeast and multicellular hydra, undergo budding ( Figure below ).
What planet, covered by a thick layer of clouds, looks smooth and featureless through a telescope?	mars	Earth	uranus	venus	Viewed through a telescope, Venus looks smooth and featureless. The planet is covered by a thick layer of clouds. You can see the clouds in pictures of Venus, such as Figure below . We make maps of the surface using radar, because the thick clouds won’t allow us to take photographs of the surface of Venus.
What type of power is generated via underground sources of heat?	solar	hydrothermal	volcanic	geothermal	Geothermal energy is an excellent resource in some parts of the world. Iceland is gets about one fourth of its electricity from geothermal sources. In the United States, California leads all states in producing geothermal energy. Geothermal energy in California is concentrated in the northern part of the state. The largest plant is in the Geysers Geothermal Resource Area. Geothermal energy is not economical everywhere. Many parts of the world do not have underground sources of heat that are close enough to the surface for building geothermal power plants.
Saturn is made mostly of what two elements?	nitrogen and boron	carbon and oxygen	helium and lithium	hydrogen and helium	Saturn’s composition is similar to Jupiter's. The planet is made mostly of hydrogen and helium. These elements are gases in the outer layers and liquids in the deeper layers. Saturn may also have a small solid core. Saturn's upper atmosphere has clouds in bands of different colors. These clouds rotate rapidly around the planet. But Saturn has fewer storms than Jupiter. Thunder and lightning have been seen in the storms on Saturn.
A homogeneous mixture composed of two or more substances is called a what?	structure	mixture	element	solution	Water is one of the most common ingredients in solutions. A solution is a homogeneous mixture composed of two or more substances. In a solution, one substance is dissolved in another substance, forming a mixture that has the same proportion of substances throughout. The dissolved substance in a solution is called the solute . The substance in which it is dissolved is called the solvent . An example of a solution in which water is the solvent is salt water. In this solution, a solid—sodium chloride—is the solute. In addition to a solid dissolved in a liquid, solutions can also form with solutes and solvents in other states of matter. Examples are given in the Table below .
What is the term for particles composed of three quarks?	tachyons	mesons	nucleons	baryons	Particles that are composed of three quarks are called baryons.
Both glyceraldehyde and glyceric acid are derivatives of biochemical intermediates in metabolism of what?	proteins	lipids	fats	sugar	Both glyceraldehyde and glyceric acid are derivatives of biochemical intermediates in sugar metabolism. Is the conversion of glycerol to glyceric acid an oxidative process or a reductive process? b. How many of these compounds are chiral? Indicate any chiral centers with an asterisk.
Instead of insects, crustaceans are the dominant arthropods in what environment?	arid habitat	tundra habitat	desert habitat	marine habitat	null
The scientific method deals with systematic investigation, reproducible results, the formation and testing of hypotheses, and what two categories of reasoning?	existence and deduction	method and deduction	reduction and deduction	induction and deduction	2.2 Nature of science Science is a methodology for learning about the world. It involves the application of knowledge. The scientific method deals with systematic investigation, reproducible results, the formation and testing of hypotheses, and reasoning. Reasoning can be broken down into two categories, induction (specific data is used to develop a generalized observation or conclusion) and deduction (general information leads to specific conclusion). Most reasoning in science is done through induction. Science as we now know it arose as a discipline in the 17th century.
What is an example of a predator-prey relationship that helps maintain the balance of organisms in ecosystems?	lion and grass	zebra and elephant	zebra and air	lion and zebra	Predation is another mechanism in which species interact with each other. Predation is when a predator organism feeds on another living organism or organisms, known as prey . The predator always lowers the prey’s fitness . It does this by keeping the prey from surviving, reproducing, or both. Predator-prey relationships are essential to maintaining the balance of organisms in an ecosystem. Examples of predator-prey relationships include the lion and zebra, the bear and fish, and the fox and rabbit.
The 'boy in the bubble' is a classic example of someone suffering what type of disease that can cause opportunistic infections?	hydroencephaly	muscular dystrophy	retardation	inherited immunodeficiency	Inherited Immunodeficiencies A list of all inherited immunodeficiencies is well beyond the scope of this book. The list is almost as long as the list of cells, proteins, and signaling molecules of the immune system itself. Some deficiencies, such as those for complement, cause only a higher susceptibility to some Gram-negative bacteria. Others are more severe in their consequences. Certainly, the most serious of the inherited immunodeficiencies is severe combined immunodeficiency disease (SCID). This disease is complex because it is caused by many different genetic defects. What groups them together is the fact that both the B cell and T cell arms of the adaptive immune response are affected. Children with this disease usually die of opportunistic infections within their first year of life unless they receive a bone marrow transplant. Such a procedure had not yet been perfected for David Vetter, the “boy in the bubble,” who was treated for SCID by having to live almost his entire life in a sterile plastic cocoon for the 12 years before his death from infection in 1984. One of the features that make bone marrow transplants work as well as they do is the proliferative capability of hematopoietic stem cells of the bone marrow. Only a small amount of bone marrow from a healthy donor is given intravenously to the recipient. It finds its own way to the bone where it populates it, eventually reconstituting the patient’s immune system, which is usually destroyed beforehand by treatment with radiation or chemotherapeutic drugs. New treatments for SCID using gene therapy, inserting nondefective genes into cells taken from the patient and giving them back, have the advantage of not needing the tissue match required for standard transplants. Although not a standard treatment, this approach holds promise, especially for those in whom standard bone marrow transplantation has failed.
What phase does dna replication occur in the cell cycle?	Mitosis	Gap 0	apoptosis	synthesis	DNA replication occurs during the S phase (the Synthesis phase) of the cell cycle, before mitosis and cell division. The base pairing rules are crucial for the process of replication. DNA replication occurs when DNA is copied to form an identical molecule of DNA.
What type of rocks form when magma cools and forms crystals?	seismic	sedimentary	metarmorphic	igneous	Igneous rocks form when magma cools and forms crystals. These rocks can form at Earth’s surface or deep underground. Figure below shows a landscape in California’s Sierra Nevada that consists entirely of granite.
What determines the color of a star?	age of the star	size of the star	core temperature	surface temperature	The color of a star is determined by its surface temperature.
Why do birds build nests?	hatch eggs	get off ground	raise birds	safe place	Birds and wasps build nests to have a safe place to store their eggs and raise their young. Many other animals build nests for the same reason. Animals protect their young in other ways, as well. For example, a mother dog not only nurses her puppies. She also washes them with her tongue and protects them from strange people or other animals. All of these behaviors help the young survive and grow up to be adults.
Flagella, cilia and pseudopods are appendages that protists use for what purpose?	momentum	gravity	pressure	movement	Most protists have motility . This is the ability to move. Protists have three types of appendages for movement. As shown in Figure below , they may have flagella, cilia , or pseudopods (“false feet”). There may be one or more whip-like flagella. Cilia are similar to flagella, except they are shorter and there are more of them. They may completely cover the surface of the protist cell. Pseudopods are temporary, foot-like extensions of the cytoplasm.
Another interesting phenomenon associated with polarized light is the ability of some crystals to split an unpolarized beam of light into two. such crystals are said to be this?	opaque matter	reflective	phosphorescent	birefringent	Another interesting phenomenon associated with polarized light is the ability of some crystals to split an unpolarized beam of light into two. Such crystals are said to be birefringent (see Figure 27.50). Each of the separated rays has a specific polarization. One behaves normally and is called the ordinary ray, whereas the other does not obey Snell’s law and is called the extraordinary ray. Birefringent crystals can be used to produce polarized beams from unpolarized light. Some birefringent materials preferentially absorb one of the polarizations. These materials are called dichroic and can produce polarization by this preferential absorption. This is fundamentally how polarizing filters and other polarizers work. The interested reader is invited to further pursue the numerous properties of materials related to polarization.
A mitotic spindle forms from the what?	ribosomes	sister chromatids	centrioles	centrosomes	A mitotic spindle forms from the centrosomes. The nuclear envelope dissolves. Chromosomes attach to the mitotic spindle, which separates the chromosomes and elongates the cell.
What is the transfer of thermal energy between objects that have different temperatures?	sweat	humidity	warm	heat	Heat is the transfer of thermal energy between objects that have different temperatures. Thermal energy always moves from an object with a higher temperature to an object with a lower temperature. Specific heat is the amount of energy (in joules) needed to raise the temperature of 1 gram of a substance by 1°C. Substances differ in their specific heat.
What is the process in which cells make proteins called?	respiration	catalysis	apoptosis	synthesis	The process in which cells make proteins is called protein synthesis . It actually consists of two processes: transcription and translation. Transcription takes place in the nucleus. It uses DNA as a template to make an RNA molecule. RNA then leaves the nucleus and goes to a ribosome in the cytoplasm, where translation occurs. Translation reads the genetic code in mRNA and makes a protein.
Living things on the ocean floor are known as?	newts	decomposers	protozoa	benthos	Benthos are living things on the ocean floor. Many benthic organisms attach themselves to rocks and stay in one place. This protects them from crashing waves and other water movements. Some benthic organisms burrow into sediments for food or protection. Benthic animals may crawl over the ocean floor. Examples of benthos include clams and worms. Figure below shows two other examples.
A double form of what reproductive process is unique to angiosperms?	infection	stimulation	destruction	fertilization	Figure 14.26 This diagram shows the lifecycle of an angiosperm. Anthers and ovaries are structures that shelter the actual gametophytes: the pollen grain and embryo sac. Double fertilization is a process unique to angiosperms. (credit: modification of work by Mariana Ruiz Villareal).
What is the term for the conversion of a liquid to its vapor below the boiling temperature of the liquid?	oxidation	absorption	vaporization	evaporation	Evaporation is the conversion of a liquid to its vapor below the boiling temperature of the liquid.
What kind of energy conversion is done by a fuel cell?	electrical into nuclear	wind into nuclear	solar into chemical	chemical into electrical	Fuel Cells A fuel cell is a device that converts chemical energy into electrical energy. Fuel cells are similar to batteries but require a continuous source of fuel, often hydrogen. They will continue to produce electricity as long as fuel is available. Hydrogen fuel cells have been used to supply power for satellites, space capsules, automobiles, boats, and submarines (Figure 17.15).
In which aspect does molality differ from molarity?	complexity	numerator	accuracy	denominator	Molality differs from molarity only in the denominator. While molarity is based on the liters of solution, molality is based on the kilograms of solvent. Concentrations expressed in molality are used when studying properties of solutions related to vapor pressure and temperature changes. Molality is used because its value does not change with changes in temperature. The volume of a solution, on the other hand, is slightly dependent upon temperature.
What is the mass that is "lost" in fission or fusion actually converted to?	hydrogen	momentum	pressure	energy	When the nucleus of a radioisotope undergoes fission or fusion, it loses a tiny amount of mass. What happens to the lost mass? It isn’t really lost at all. It is converted to energy. How much energy? . The change in mass is tiny, but it results in a great deal of energy.
What does a glacier leave behind when it retreats?	sediment	Dirt	Lakes	bare rock	a glacier retreats and leaves behind bare rock.
What law states that matter cannot be created or destroyed even when it changes?	modification of mass	Action of mass	Transfer of mass	conservation of mass	Matter cannot be created or destroyed even when it changes. This is the law of conservation of mass.
What are natural sponges made of?	sea shells	sand	sea plants	sea animals	Natural sponges, like the one in the picture above, are actually animals taken from the sea! The sponges in your home, however, were most likely never living things. Most sponges used in kitchens today are made from unnatural materials.
The process in which certain bacteria change nitrogen gas to a form that plants can absorb through their roots is known as what?	dioxide fixation	pollen fixation	oxygen fixation	nitrogen fixation	Even though nitrogen gas makes up most of Earth's atmosphere, plants cannot use this nitrogen gas to make organic compounds for themselves and other organisms. The two nitrogen atoms in a molecule of nitrogen gas are held together by a very stable triple bond. This bond must be broken for the nitrogen to be used. The nitrogen gas must be changed to a form called nitrates, which plants can absorb through their roots. The process of changing nitrogen gas to nitrates is called nitrogen fixation . It is carried out by nitrogen-fixing bacteria. The bacteria live in soil and roots of legumes, such as peas.
What gas is actually a waste product of photosynthesis?	nitrogen	carbon dioxide	hydrogen	oxygen	Around 3 billion years ago, photosynthesis began. Organisms could make their own food from sunlight and inorganic molecules. From these ingredients they made chemical energy that they used. Oxygen is a waste product of photosynthesis. That first oxygen combined with iron to create iron oxide. Later on, the oxygen entered the atmosphere.
Distinguished by the great red spot, what planet has an upper atmosphere containing ammonia clouds?	mars	saturn	uranus	jupiter	Jupiter's atmosphere is unlike any other in the solar system! The upper layer contains clouds of ammonia. The ammonia is different colored bands. These bands rotate around the planet. The ammonia also swirls around in tremendous storms. The Great Red Spot ( Figure below ) is Jupiter's most noticeable feature. The spot is an enormous, oval-shaped storm. It is more than three times as wide as Earth! Clouds in the storm rotate counterclockwise. They make one complete turn every six days or so. The Great Red Spot has been on Jupiter for at least 300 years. It may have been observed as early as 1664. It is possible that this storm is a permanent feature on Jupiter. No one knows for sure.
What controls what goes in and out of a cell?	the mitochondria	the cilia	the nucleus	the plasma membrane	The function of the plasma membrane is to control what goes in and out of the cell. Some molecules can go through the cell membrane to enter and leave the cell, but some cannot. The cell is therefore not completely permeable. "Permeable" means that anything can cross a barrier. An open door is completely permeable to anything that wants to enter or exit through the door. The plasma membrane is semipermeable , meaning that some things can enter the cell, and some things cannot.
If the average binding energy per nucleon overcomes the repulsion, the nucleus stays together and it referred to as what?	closed	even	solid	stable	Each nucleus, therefore, has competing forces. The repulsive force between the protons tends to blow the nucleus apart and the binding energy tends to hold the nucleus together. If the average binding energy per nucleon overcomes the repulsion, the nucleus stays together and it referred to as stable. If the repulsion overcomes the average binding energy per nucleon, the nucleus may blow apart or undergo nuclear disintegration . When a nucleus disintegrates, it throws off pieces of itself and energy in the form of gamma rays . This disintegration process came to be called radioactivity .
What is mollusks complete digestive system called?	thallus	choroid	vesicle	coelom	Mollusks also have a coelom, a complete digestive system, and specialized organs for excretion.
Kinetic energy is the energy of what?	wind	heat	light	motion	Kinetic energy is the energy of motion.
Which area in a lake is likely to have more nutrients?	surface	crust	reef	bottom	Water near the bottom of lakes and the ocean may contain more nutrients than water closer to the surface. When aquatic organisms die, they sink to the bottom. Decomposers near the bottom of the water break down the dead organisms and release their nutrients back into the water.
Temperature is a measure of how hot or cold an object is relative to another object, whereas heat is the flow of what energy between objects with different temperatures?	potential energy	nuclear energy	gravitational energy	thermal energy	Temperature The concept of temperature may seem familiar to you, but many people confuse temperature with heat. Temperature is a measure of how hot or cold an object is relative to another object (its thermal energy content), whereas heat is the flow of thermal energy between objects with different temperatures. Three different scales are commonly used to measure temperature: Fahrenheit (expressed as °F), Celsius (°C), and Kelvin (K). Thermometers measure temperature by using materials that expand or contract when heated or cooled. Mercury or alcohol thermometers, for example, have a reservoir of liquid that expands when heated and contracts when cooled, so the liquid column lengthens or shortens as the temperature of the liquid changes.
Scientists use seismographs and intersecting circles to determine the location of what?	volcano	tsunami	hurricane	earthquake epicenter	Next, the seismologists try to determine the location of the earthquake epicenter. To do this they need the distances to the epicenter from at least three seismographs. Let’s say that they know that an earthquake’s epicenter is 50 kilometers from Kansas City. They draw a circle with a 50 km radius around that seismic station. They do this twice more around two different seismic stations. The three circles intersect at a single point. This is the earthquake’s epicenter ( Figure below ).
What happens when iron is exposed to water and oxygen?	combustion	smoking	shrinking	rusting	Corrosion involves the formation of an oxidized form of a metal by an electrochemical process. A common example is the rusting of iron when exposed to water and oxygen. The tarnishing of silver and the red or green deposits formed on copper are other examples. Corrosion in all its forms costs the U. S. millions of dollars each year in expenses for metal replacement.
What disease is generally caused by mutations in genes that regulate the cell cycle?	pneumonia	heart disease	arthritis	cancer	Cancer is a disease in which cells grow out of control and form abnormal masses of cells. It is generally caused by mutations in genes that regulate the cell cycle. Because of the mutations, cells with damaged DNA are allowed to divide without limits. Cancer causing genes can be inherited. You can learn more about hereditary cancer by watching the video at the following link: http://www. youtube. com/watch?v=LWk5FplsKwM (4:29).
Proteins are organic compounds made up of what type of acids?	lactic	nucleic	enzyme	amino	Proteins are organic compounds made up of amino acids. They form muscles, speed up chemical reactions, and perform many other cellular functions.
Speciation is usually due to a single instance of what?	radiation	division	accumulation	mutation	null
What is the name of the extra layer that prokaryotes have outside the cell wall?	a shell	a bone	a shape	a capsule	Many prokaryotes have an extra layer, called a capsule, outside the cell wall. The capsule protects the cell from chemicals and from drying out. It also allows the cell to stick to surfaces and to other cells. Because of this, many prokaryotes can form biofilms, like the one shown in Figure below . A biofilm is a colony of prokaryotes that is stuck to a surface such as a rock or a host’s tissues. The sticky plaque that collects on your teeth between brushings is a biofilm. It consists of millions of bacteria.
The binary halides are an important subclass of what?	gases	acids	minerals	salts	Halides of the Representative Metals Thousands of salts of the representative metals have been prepared. The binary halides are an important subclass of salts. A salt is an ionic compound composed of cations and anions, other than hydroxide or oxide ions. In general, it is possible to prepare these salts from the metals or from oxides, hydroxides, or carbonates. We will illustrate the general types of reactions for preparing salts through reactions used to prepare binary halides. The binary compounds of a metal with the halogens are the halides. Most binary halides are ionic. However, mercury, the elements of group 13 with oxidation states of 3+, tin(IV), and lead(IV) form covalent binary halides. The direct reaction of a metal and a halogen produce the halide of the metal. Examples of these oxidation-reduction reactions include: Cd(s) + Cl 2(g) ⟶ CdCl 2(s) 2Ga(l) + 3Br 2(l) ⟶ 2GaBr 3(s).
When was construction of the hoover dam completed?	1905	1959	1969	1935	If you take a trip out of Las Vegas toward Phoenix you can visit the Hoover Dam. Completed in 1935, the dam provides power to over a million homes. It also stores water for use by the residents of the desert southwest. Hoover Dam is one of the engineering marvels of the 20th century.
Some plants can produce seeds without fertilization and this method of reproduction is known as what?	Density	gametes	amoebas	apomixis	Some plants can produce seeds without fertilization. Either the ovule or part of the ovary, which is diploid in nature, gives rise to a new seed. This method of reproduction is known as apomixis. An advantage of asexual reproduction is that the resulting plant will reach maturity faster. Since the new plant is arising from an adult plant or plant parts, it will also be sturdier than a seedling. Asexual reproduction can take place by natural or artificial (assisted by humans) means.
What type of chains do unsaturated fatty acids have?	Broken Chains	Spiral Chains	Stait Chains	bent chains	Fatty Acids. Saturated fatty acids have straight chains, like the three fatty acids shown in the upper left. Unsaturated fatty acids have bent chains, like all the other fatty acids in the figure.
Ribosomes are the site of what process?	Measure Synthesis	organism synthesis	consume synthesis	protein synthesis	8.5 Ribosomes Ribosomes are the site of protein synthesis. Ribosomes themselves are synthesized in the cell nucleoli28 and are structured as two subunits, the large and the small. These parts are composed of RNA and protein. Prokaryotic and eukaryotic ribosomes are different, the eukaryotic ones being larger and more complicated.
Bacteria and archaea that survive under extreme conditions are called?	carotenoids	audiophiles	rotifers	extremophiles	phototrophs and began the oxygenation of the atmosphere. The increase in oxygen concentration allowed the evolution of other life forms. Fossilized microbial mats are called stromatolites and consist of laminated organo-sedimentary structures formed by precipitation of minerals by prokaryotes. They represent the earliest fossil record of life on Earth. Bacteria and archaea grow in virtually every environment. Those that survive under extreme conditions are called extremophiles (extreme lovers). Some prokaryotes cannot grow in a laboratory setting, but they are not dead. They are in the viable-but-non-culturable (VBNC) state. The VBNC state occurs when prokaryotes enter a dormant state in response to environmental stressors. Most prokaryotes are social and prefer to live in communities where interactions take place. A biofilm is a microbial community held together in a gummy-textured matrix.
The production and transport of gametes is performed by what type of organs?	digestion	degradation	skin	reproductive	46.3 Reproductive organs produce and transport gametes.
What are atoms of the same element but with different numbers of neutrons called?	electrons	variations	masses	isotopes	Isotopes are atoms of the same element but with different numbers of neutrons.
Active transport mechanisms require the use of the cell’s energy, usually in the form of what?	protein	ribonucleic acid (RNA)	deoxyribonucleic acid (DNA)	adenosine triphosphate (atp	3.6 \| Active Transport By the end of this section, you will be able to: • Understand how electrochemical gradients affect ions • Describe endocytosis, including phagocytosis, pinocytosis, and receptor-mediated endocytosis • Understand the process of exocytosis Active transport mechanisms require the use of the cell’s energy, usually in the form of adenosine triphosphate (ATP). If a substance must move into the cell against its concentration gradient, that is, if the concentration of the substance inside the cell must be greater than its concentration in the extracellular fluid, the cell must use energy to move the substance. Some active transport mechanisms move small-molecular weight material, such as ions, through the membrane. In addition to moving small ions and molecules through the membrane, cells also need to remove and take in larger molecules and particles. Some cells are even capable of engulfing entire unicellular microorganisms. You might have correctly hypothesized that the uptake and release of large particles by the cell requires energy. A large particle, however, cannot pass through the membrane, even with energy supplied by the cell.
What kind of energy can move through glass much better than through paper?	heat	vibrational	sound	light	null
What forms when one substance dissolves into another?	solvent	mixture	compound	solution	When one substance dissolves into another, a solution is formed. A solution is a homogeneous mixture consisting of a solute dissolved into a solvent . The solute is the substance that is being dissolved, while the solvent is the dissolving medium. Solutions can be formed with many different types and forms of solutes and solvents.
What transition occurs as heat is added or removed from a substance?	heat wave	thermal reaction	diffusion transition	phase transition	Phase transitions occur as heat is added or removed from a substance.
What is the predicted year that as many as half of all remaining species could go extinct?	2020	3000	2040	2050	Evidence shows that a sixth mass extinction is happening right now. Species are currently going extinct at the fastest rate since the dinosaurs died out. Dozens of species are going extinct every day. If this rate continues, as many as half of all remaining species could go extinct by 2050.

Which trait of particles causes even cold objects to have some thermal energy?

kinetic energy

equilibrium

momentum

constant random motion

Scientists think that multicellularity arose from cooperation between many organisms of the same species. The Colonial Theory proposes that this cooperation led to the development of a multicellular organism. Many examples of cooperation between organisms in nature have been observed. For example, a certain species of amoeba (a single-celled protist) groups together during times of food shortage and forms a colony that moves as one to a new location. Some of these amoebas then become slightly differentiated from each other. Volvox, shown in Figure above , is another example of a colonial organism. Most scientists accept that the Colonial theory explains how multicellular organisms evolved.

Found in many electric devices, what is a coil of wire wrapped around a bar of iron or other ferromagnetic material?

actuator

battery

superconductor

electromagnet

The animal mole is very different than the counting unit of the mole. Chemists nonetheless have adopted the mole as their unofficial mascot. National Mole Day is a celebration of chemistry that occurs on October 23rd (10/23) of each year.

What is it called when two organisms live close together and form a relationship?

Family

definitions

traits

symbiosis

Fungi don't live in isolation. They often interact with other species. In fact, fungi can be dependent on another organism for survival. When two species live close together and form a relationship, it is called symbiosis . Symbiosis can be beneficial to one or both organisms, or sometimes one organism hurts the other. Some of the partners in these relationships include plants, algae, insects and other animals, and even humans.

What does fsh help stimulate in the ovaries and sperm in the testes?

spawning

in vitro fertilization

dna replication

maturation of eggs

Peptide and Protein Hormones Whereas the amine hormones are derived from a single amino acid, peptide and protein hormones consist of multiple amino acids that link to form an amino acid chain. Peptide hormones consist of short chains of amino acids, whereas protein hormones are longer polypeptides. Both types are synthesized like other body proteins: DNA is transcribed into mRNA, which is translated into an amino acid chain. Examples of peptide hormones include antidiuretic hormone (ADH), a pituitary hormone important in fluid balance, and atrial-natriuretic peptide, which is produced by the heart and helps to decrease blood pressure. Some examples of protein hormones include growth hormone, which is produced by the pituitary gland, and follicle-stimulating hormone (FSH), which has an attached carbohydrate group and is thus classified as a glycoprotein. FSH helps stimulate the maturation of eggs in the ovaries and sperm in the testes.

The largest phylum of the animal kingdom is what?

crustaceans

cephalopods

mammals

arthropods

Arthropods are not only the largest phylum of invertebrates. They are by far the largest phylum of the animal kingdom. Roughly 80 percent of all animal species living on Earth today are arthropods. Obviously, arthropods have been extremely successful. What accounts for their success?.

During what process is light from the star focused and the star appears to brighten in a characteristic manner?

macrolensing

spectrometry

excitation

microlensing

In a process called microlensing, light from the star is focused and the star appears to brighten in a characteristic manner. Searches for dark matter in this form are particularly interested in galactic halos because of the huge amount of mass that seems to be there. Such microlensing objects are thus called massive compact halo objects, or MACHOs. To date, a few MACHOs have been observed, but not predominantly in galactic halos, nor in the numbers needed to explain dark matter. MACHOs are among the most conventional of unseen objects proposed to explain dark matter. Others being actively pursued are red dwarfs, which are small dim stars, but too few have been seen so far, even with the Hubble Telescope, to be of significance. Old remnants of stars called white dwarfs are also under consideration, since they contain about a solar mass, but are small as the Earth and may dim to the point that we ordinarily do not observe them. While white dwarfs are known, old dim ones are not. Yet another possibility is the existence of large numbers of smaller than stellar mass black holes left from the Big Bang—here evidence is entirely absent. There is a very real possibility that dark matter is composed of the known neutrinos, which may have small, but finite, masses. As discussed earlier, neutrinos are thought to be massless, but we only have upper limits on their masses, rather than knowing they are exactly zero. So far, these upper limits come from difficult measurements of total energy emitted in the decays and reactions in which neutrinos are involved. There is an amusing possibility of proving that neutrinos have mass in a completely different way. We have noted in Particles, Patterns, and Conservation Laws that there are three flavors of neutrinos ( ν e ,.

Much like the processes of dna replication and transcription, translation consists of three main stages: initiation, elongation, and this?

detonation

isolation

assimilation

termination

Much like the processes of DNA replication and transcription, translation consists of three main stages: initiation, elongation, and termination. Initiation takes place with the binding of a ribosome to an mRNA transcript. The elongation stage involves the recognition of a tRNA anticodon with the next mRNA codon in the sequence. Once the anticodon and codon sequences are bound (remember, they are complementary base pairs), the tRNA presents its amino acid cargo and the growing polypeptide strand is attached to this next amino acid. This attachment takes place with the assistance of various enzymes and requires energy. The tRNA molecule then releases the mRNA strand, the mRNA strand shifts one codon over in the ribosome, and the next appropriate tRNA arrives with its matching anticodon. This process continues until the final codon on the mRNA is reached which provides a “stop” message that signals termination of translation and triggers the release of the complete, newly synthesized protein. Thus, a gene within the DNA molecule is transcribed into mRNA, which is then translated into a protein product (Figure 3.29).

Each hemisphere of the cerebrum consists of four parts, called what?

quarters

rows

layers

lobes

Each hemisphere of the cerebrum consists of four parts, called lobes. Each lobe is associated with particular brain functions. Just one function of each lobe is listed here.

What is an organic compound that is the primary component of natural gas?

sulfur

ethanol

magnesium

methane

Methane is an organic compound that is the primary component of natural gas. Its structure consists of a central carbon atom with four single bonds to hydrogen atoms (see Figure below ). In order to maximize their distance from one another, the four groups of bonding electrons do not lie in the same plane. Instead, each of the hydrogen atoms lies at the corners of a geometrical shape called a tetrahedron. The carbon atom is at the center of the tetrahedron. Each face of a tetrahedron is an equilateral triangle.

What is raising the temperature of earth’s surface?

Coriolis effect

ozone layer

photosynthesis effect

greenhouse effect

Gases such as carbon dioxide from the burning of fossil fuels increase the natural greenhouse effect. This is raising the temperature of Earth’s surface, and is called global warming.

What is a measure of randomness or disorder in a system?

chaos theory

enthropy

biodiversity

entropy

Figure 6.12 Entropy is a measure of randomness or disorder in a system. Gases have higher entropy than liquids, and liquids have higher entropy than solids.

What is the distance between two corresponding points of adjacent waves called?

variation

wave distance

bandwidth

wavelength

Wave amplitude is the maximum distance the particles of a medium move from their resting positions as a wave passes through. Wavelength is the distance between two corresponding points of adjacent waves. Waves with greater amplitudes or shorter wavelengths have more energy.

Crossing-over is the exchange of genetic material between which chromosomes?

analogous

metacentric

monogamous

homologous

When homologous chromosomes form pairs during prophase I of meiosis I, crossing-over can occur. Crossing-over is the exchange of genetic material between homologous chromosomes. It results in new combinations of genes on each chromosome.

What is a ridge of sand that extends away from the shore?

a scoop

a dig

a depression

a spit

A spit is a ridge of sand that extends away from the shore. The end of the spit may hook around toward the quieter waters close to shore.

Manganin is made up of metals that include copper, manganese and nickel - what do you generally call a metal of this type?

mixed metal

complex metal

silicon

alloy

for metals, meaning their resistivity increases with temperature. Some alloys have been developed specifically to have a small temperature dependence. Manganin (which is made of copper, manganese and nickel), for example, has α close to zero (to three digits on the scale in Table 20.2), and so its resistivity varies only slightly with temperature. This is useful for making a temperature-independent resistance standard, for example.

Protons and neutrons are located in which central part of the atom?

radius

shell

nucleolus

nucleus

Electrons have almost no mass. Instead, almost all the mass of an atom is in its protons and neutrons in the nucleus. The nucleus is very small, but it is densely packed with matter. The SI unit for the mass of an atom is the atomic mass unit (amu) . One atomic mass unit equals the mass of a proton, which is about 1.7 × 10 -24 g. Each neutron also has a mass of 1 amu. Therefore, the sum of the protons and neutrons in an atom is about equal to the atom’s total mass in atomic mass units.

Cancer is the result of unchecked cell division caused by a breakdown of the mechanisms that regulate this?

respiration

blood flow

digestion

cell cycle

10.4 Cancer and the Cell Cycle Cancer is the result of unchecked cell division caused by a breakdown of the mechanisms that regulate the cell cycle. The loss of control begins with a change in the DNA sequence of a gene that codes for one of the regulatory molecules. Faulty instructions lead to a protein that does not function as it should. Any disruption of the monitoring system can allow other mistakes to be passed on to the daughter cells. Each successive cell division will give rise to daughter cells with even more accumulated damage. Eventually, all checkpoints become nonfunctional, and rapidly reproducing cells crowd out normal cells, resulting in a tumor or leukemia (blood cancer).

Slabs of continents moving around on earth's surface is called what?

fault tectonics

edge tectonics

crator tectonics

plate tectonics

Plate tectonics theory says that slabs of continents move around on Earth's surface. The mechanism for that movement is seafloor spreading. Plate tectonics explain many things about Earth: (1) geological activity, why it happens where it does; (2) natural resources, why many are found where they are; and (3) the past and future, what happened in the past and what will happen in the future. The theory of plate tectonics will be explored in the chapter Plate Tectonics .

In plants, what structure located above the root cap is where growth in length occurs?

elections meristem

secondary meristem

support meristem

primary meristem

As shown in Figure below , the tip of a root is called the root cap. It consists of specialized cells that help regulate primary growth of the root at the tip. Above the root cap is primary meristem, where growth in length occurs.

With what does an electromagnetic wave start?

battery

kinetic energy

static charged particle

vibrating charged particle

An electromagnetic wave starts with a vibrating charged particle.

What kind of overdose do eudicots die from?

chemical

nutritional

metabolic

hormonal

null

The particles in a colloid are large enough to scatter light, a phenomenon called what?

bowman effect

astral effect

jonah effect

tyndall effect

The particles in a colloid are large enough to scatter light, a phenomenon called the Tyndall effect. This can make colloidal mixtures appear cloudy or opaque, such as the searchlight beams shown in Figure 11.31. Clouds are colloidal mixtures. They are composed of water droplets that are much larger than molecules, but that are small enough that they do not settle out.

What two things limit primary production in aquatic ecosystems?

air and light

air and nutrients

pollution and nutrients

light and nutrients

null

Vascular and non-vascular are two groups of what kind of organism?

fungi

animals

vertebrates

plants

The Major Divisions of Land Plants The green algae and land plants are grouped together into a subphylum called the Streptophytina, and thus are called Streptophytes. In a further division, land plants are classified into two major groups according to the absence or presence of vascular tissue, as detailed in Figure 25.6. Plants that lack vascular tissue, which is formed of specialized cells for the transport of water and nutrients, are referred to as non-vascular plants. Liverworts, mosses, and hornworts are seedless, non-vascular plants that likely appeared early in land plant evolution. Vascular plants developed a network of cells that conduct water and solutes. The first vascular plants appeared in the late Ordovician and were probably similar to lycophytes, which include club mosses (not to be confused with the mosses) and the pterophytes (ferns, horsetails, and whisk ferns). Lycophytes and pterophytes are referred to as seedless vascular plants, because they do not produce seeds. The seed plants, or spermatophytes, form the largest group of all existing plants, and hence dominate the landscape. Seed plants include gymnosperms, most notably conifers (Gymnosperms), which produce “naked seeds,” and the most successful of all plants, the flowering plants (Angiosperms). Angiosperms protect their seeds inside chambers at the center of a flower; the walls of the chamber later develop into a fruit.

The burning of fossil fuels has increased which effect?

ozone effect

natural gas effect

photosynthesis effect

greenhouse effect

The burning of fossil fuels has increased the greenhouse effect and caused global climate change. Increasing temperatures are changing basic climate factors of habitats, and rising sea levels are covering them with water. These changes threaten many species.

What do you call geographical areas that contain high numbers of endemic species?

endospots

warmspots

multispots

hotspots

A simple measure of success in setting aside preserves for biodiversity protection is to set a target percentage of land or marine habitat to protect. However, a more detailed preserve design and choice of location is usually necessary because of the way protected lands are allocated and how biodiversity is distributed: protected lands tend to contain less economically valuable resources rather than being set aside specifically for the species or ecosystems at risk. In 2003, the IUCN World Parks Congress estimated that 11.5 percent of Earth’s land surface was covered by preserves of various kinds. This area is greater than previous goals; however, it only represents 9 out of 14 recognized major biomes and research has shown that 12 percent of all species live outside preserves; these percentages are much higher when threatened species are considered and when only high quality preserves are considered. For example, high quality preserves include only about 50 percent of threatened amphibian species. The conclusion must be that either the percentage of area protected must be increased, the percentage of high quality preserves must be increased, or preserves must be targeted with greater attention to biodiversity protection. Researchers argue that more attention to the latter solution is required. A biodiversity hotspot is a conservation concept developed by Norman Myers in 1988. Hotspots are geographical areas that contain high numbers of endemic species. The purpose of the concept was to identify important locations on the planet.

What type of climate do most agaves grow in?

tropical

arctic

rainforest

arid

null

What cells secrete signaling molecules that promote sperm production and can control whether germ cells live or die?

egg cells

erythrocytes

neurons

sertoli cells

Sertoli Cells Surrounding all stages of the developing sperm cells are elongate, branching Sertoli cells. Sertoli cells are a type of supporting cell called a sustentacular cell, or sustenocyte, that are typically found in epithelial tissue. Sertoli cells secrete signaling molecules that promote sperm production and can control whether germ cells live or die. They extend physically around the germ cells from the peripheral basement membrane of the seminiferous tubules to the lumen. Tight junctions between these sustentacular cells create the blood–testis barrier, which keeps bloodborne substances from reaching the germ cells and, at the same time, keeps surface antigens on developing germ cells from escaping into the bloodstream and prompting an autoimmune response.

Invertebrate chordates use what to filter food out of water?

nose

pores

tails

gills

Invertebrate chordates use their gills to filter food out of water, not to absorb oxygen. In the early evolution of fish, there was a switch to using gills to absorb oxygen instead of to filter food. Gills consist of many thin, folded tissues that provide a large surface area for oxygen uptake. With more oxygen absorbed by the gills, fish could become much larger and more active.

Because the current is alternating, the magnetic field of the iron core keeps doing what?

decreasing

increasing

changing

reversing

The transformer in the diagram consists of two wire coils wrapped around an iron core. Each coil is part of a different circuit. When alternating current passes through coil P, it magnetizes the iron core. Because the current is alternating, the magnetic field of the iron core keeps reversing. This is where electromagnetic induction comes in. The changing magnetic field induces alternating current in coil S of the other circuit.

When heat moves out of a system, what is the sign of the enthalpy?

N/A (zero)

it depends

positive

negative

where H is the enthalpy of the system, E is the internal energy, P is the pressure, and V is the volume. It can be difficult to distinguish "heat" and "enthalpy. " Heat measures the transfer of thermal energy between two objects, and enthalpy measures the flow of heat. When heat flows out of a system, the change in enthalpy is negative; when heat flows into a system, the change in enthalpy is positive. Enthalpy is a useful tool for characterizing chemical reactions.

What occurs when light bumps into tiny particles of matter and spreads out in all directions?

rainbow effect

kaleidoscope

darkness

scattering

Scattering occurs when light bumps into tiny particles of matter and spreads out in all directions. In the Figure below , beams of light from car headlights are shining through fog. The light is scattered by water droplets in the air, giving the headlights a “halo” appearance.

During unfavorable conditions, mature seeds may enter a period of inactivity or extremely low metabolic activity called what?

malignancy

hibernation

germination

dormancy

Seed Germination Many mature seeds enter a period of inactivity, or extremely low metabolic activity: a process known as dormancy, which may last for months, years or even centuries. Dormancy helps keep seeds viable during unfavorable conditions. Upon a return to favorable conditions, seed germination takes place. Favorable conditions could be as diverse as moisture, light, cold, fire, or chemical treatments. After heavy rains, many new seedlings emerge. Forest fires also lead to the emergence of new seedlings. Some seeds require vernalization (cold treatment) before they can germinate. This guarantees that seeds produced by plants in temperate climates will not germinate until the spring. Plants growing in hot climates may have seeds that need a heat treatment in order to germinate, to avoid germination in the hot, dry summers. In many seeds, the presence of a thick seed coat retards the ability to germinate. Scarification, which includes mechanical or chemical processes to soften the seed coat, is often employed before germination. Presoaking in hot water, or passing through an acid environment, such as an animal’s digestive tract, may also be employed. Depending on seed size, the time taken for a seedling to emerge may vary. Species with large seeds have enough food reserves to germinate deep below ground, and still extend their epicotyl all the way to the soil surface. Seeds of smallseeded species usually require light as a germination cue. This ensures the seeds only germinate at or near the soil surface (where the light is greatest). If they were to germinate too far underneath the surface, the developing seedling would not have enough food reserves to reach the sunlight.

Solid coal, liquid petroleum, and liquid natural gas are all types of what?

solar electric

nuclear fusion

hydroelectric

fossil fuels

Fossil fuels include solid coal, liquid petroleum, and liquid natural gas.

What everyday beverage commodity is second only to oil in worldwide trade?

beer

water

soda

coffee

Chemistry in Everyday Life Decaffeinating Coffee Using Supercritical CO2 Coffee is the world’s second most widely traded commodity, following only petroleum. Across the globe, people love coffee’s aroma and taste. Many of us also depend on one component of coffee—caffeine—to help us get going in the morning or stay alert in the afternoon. But late in the day, coffee’s stimulant effect can keep you from sleeping, so you may choose to drink decaffeinated coffee in the evening. Since the early 1900s, many methods have been used to decaffeinate coffee. All have advantages and disadvantages, and all depend on the physical and chemical properties of caffeine. Because caffeine is.

Where are ribosomes made?

protoplasm

cell membrane

mitochondria

the nucleolus

The nucleolus is inside the nucleus, and is where ribosomes are made.

What prevents loss of water from the body and keeps out microorganisms?

sweat

muscles

hydration

the skin'

The skin prevents loss of water from the body and keeps out microorganisms. Melanin in the epidermis protects the dermis from damaging ultraviolet light. By dilating or contracting its blood vessels and releasing sweat, skin helps maintain a constant body temperature.

Batteries containing a liquid electrolyte, like those in cars, are referred to as what kind of battery?

lithium cell

time cell

sand cell

wet cell

The car battery is an example of a “wet cell” battery, because there is a liquid electrolyte (sulfuric acid) present in the system. These batteries must operate in an upright position so the liquid material does not spill out. In contrast, dry cell batteries contain a paste that serves as the positive electrode. The composition and voltage depends on the specific battery, but typical voltage outputs are in the 1.0-1.5 volt range.

Stp, which is important in determining information about gas behavior and properties, stands for standard temperature and what?

push

pull

power

pressure

It should be obvious by now that some physical properties of gases depend strongly on the conditions. What we need is a set of standard conditions so that properties of gases can be properly compared to each other. Standard temperature and pressure (STP) is defined as exactly 100 kPa of pressure (0.986 atm) and 273 K (0°C). For simplicity, we will use 1 atm as standard pressure. Defining STP allows us to compare more directly the properties of gases that differ from each other. One property shared among gases is a molar volume. The molar volume is the volume of 1 mol of a gas. At STP, the molar volume of a gas can be easily determined by using the ideal gas law:.

Within a particular habitat, what can be characterized by its size or density?

percent

total

group

population

Population Size and Density The study of any population usually begins by determining how many individuals of a particular species exist, and how closely associated they are with each other. Within a particular habitat, a population can be characterized by its population size (N), the total number of individuals, and its population density, the number of individuals within a specific area or volume. Population size and density are the two main characteristics used to describe and understand populations. For example, populations with more individuals may be more stable than smaller populations based on their genetic variability, and thus their potential to adapt to the environment. Alternatively, a member of a population with low population density (more spread out in the habitat), might have more difficulty finding a mate to reproduce compared to a population of higher density. As is shown in Figure 45.2, smaller organisms tend to be more densely distributed than larger organisms.

Animals that eat decomposing organic material, such as dung beetles, make the material available to what organisms that break it down further?

protozoa

consumers

pathogens

bacteria

Animals that eat decomposing organic material also have an important interaction with the environment. They help to decompose dead matter and assist with the recycling of nutrients. By burying and eating dung, dung beetles, such as the one shown in Figure below , improve nutrient cycling and soil structure. They make the dead organic matter available to bacteria that break it down even further.

Skin that acts as camouflage or secretes chemicals poisonous to predators are successful modification in frogs and salamanders, classed as what in the order anura?

reptiles

parasites

fungi

amphibians

View River Monsters: Fish With Arms and Hands? (http://openstaxcollege. org/l/river_monster) to see a video about an unusually large salamander species. Anura: Frogs Frogs are amphibians that belong to the order Anura (Figure 29.17). Anurans are among the most diverse groups of vertebrates, with approximately 5,965 species that occur on all of the continents except Antarctica. Anurans have a body plan that is more specialized for movement. Adult frogs use their hind limbs to jump on land. Frogs have a number of modifications that allow them to avoid predators, including skin that acts as camouflage. Many species of frogs and salamanders also release defensive chemicals from glands in the skin that are poisonous to predators.

What do you call people who study science and are experts in one or more fields of science?

doctors

chemists

animals

scientists

Scientists are regular people who chose to study science. They are experts in done or more fields of science.

In budding , organisms reproduce by having new individuals split off from what?

a sister chromatid

ova

nuclei

existing ones

In budding , organisms reproduce by having new individuals split off from existing ones, which results in genetically identical parent and daughter organisms. The bud may stay attached or break free from the parent. Eukaryotic organisms, such as the single cell yeast and multicellular hydra, undergo budding ( Figure below ).

What planet, covered by a thick layer of clouds, looks smooth and featureless through a telescope?

mars

Earth

uranus

venus

Viewed through a telescope, Venus looks smooth and featureless. The planet is covered by a thick layer of clouds. You can see the clouds in pictures of Venus, such as Figure below . We make maps of the surface using radar, because the thick clouds won’t allow us to take photographs of the surface of Venus.

What type of power is generated via underground sources of heat?

solar

hydrothermal

volcanic

geothermal

Geothermal energy is an excellent resource in some parts of the world. Iceland is gets about one fourth of its electricity from geothermal sources. In the United States, California leads all states in producing geothermal energy. Geothermal energy in California is concentrated in the northern part of the state. The largest plant is in the Geysers Geothermal Resource Area. Geothermal energy is not economical everywhere. Many parts of the world do not have underground sources of heat that are close enough to the surface for building geothermal power plants.

Saturn is made mostly of what two elements?

nitrogen and boron

carbon and oxygen

helium and lithium

hydrogen and helium

Saturn’s composition is similar to Jupiter's. The planet is made mostly of hydrogen and helium. These elements are gases in the outer layers and liquids in the deeper layers. Saturn may also have a small solid core. Saturn's upper atmosphere has clouds in bands of different colors. These clouds rotate rapidly around the planet. But Saturn has fewer storms than Jupiter. Thunder and lightning have been seen in the storms on Saturn.

A homogeneous mixture composed of two or more substances is called a what?

structure

mixture

element

solution

Water is one of the most common ingredients in solutions. A solution is a homogeneous mixture composed of two or more substances. In a solution, one substance is dissolved in another substance, forming a mixture that has the same proportion of substances throughout. The dissolved substance in a solution is called the solute . The substance in which it is dissolved is called the solvent . An example of a solution in which water is the solvent is salt water. In this solution, a solid—sodium chloride—is the solute. In addition to a solid dissolved in a liquid, solutions can also form with solutes and solvents in other states of matter. Examples are given in the Table below .

What is the term for particles composed of three quarks?

tachyons

mesons

nucleons

baryons

Particles that are composed of three quarks are called baryons.

Both glyceraldehyde and glyceric acid are derivatives of biochemical intermediates in metabolism of what?

proteins

lipids

fats

sugar

Both glyceraldehyde and glyceric acid are derivatives of biochemical intermediates in sugar metabolism. Is the conversion of glycerol to glyceric acid an oxidative process or a reductive process? b. How many of these compounds are chiral? Indicate any chiral centers with an asterisk.

Instead of insects, crustaceans are the dominant arthropods in what environment?

arid habitat

tundra habitat

desert habitat

marine habitat

null

The scientific method deals with systematic investigation, reproducible results, the formation and testing of hypotheses, and what two categories of reasoning?

existence and deduction

method and deduction

reduction and deduction

induction and deduction

2.2 Nature of science Science is a methodology for learning about the world. It involves the application of knowledge. The scientific method deals with systematic investigation, reproducible results, the formation and testing of hypotheses, and reasoning. Reasoning can be broken down into two categories, induction (specific data is used to develop a generalized observation or conclusion) and deduction (general information leads to specific conclusion). Most reasoning in science is done through induction. Science as we now know it arose as a discipline in the 17th century.

What is an example of a predator-prey relationship that helps maintain the balance of organisms in ecosystems?

lion and grass

zebra and elephant

zebra and air

lion and zebra

Predation is another mechanism in which species interact with each other. Predation is when a predator organism feeds on another living organism or organisms, known as prey . The predator always lowers the prey’s fitness . It does this by keeping the prey from surviving, reproducing, or both. Predator-prey relationships are essential to maintaining the balance of organisms in an ecosystem. Examples of predator-prey relationships include the lion and zebra, the bear and fish, and the fox and rabbit.

The 'boy in the bubble' is a classic example of someone suffering what type of disease that can cause opportunistic infections?

hydroencephaly

muscular dystrophy

retardation

inherited immunodeficiency

Inherited Immunodeficiencies A list of all inherited immunodeficiencies is well beyond the scope of this book. The list is almost as long as the list of cells, proteins, and signaling molecules of the immune system itself. Some deficiencies, such as those for complement, cause only a higher susceptibility to some Gram-negative bacteria. Others are more severe in their consequences. Certainly, the most serious of the inherited immunodeficiencies is severe combined immunodeficiency disease (SCID). This disease is complex because it is caused by many different genetic defects. What groups them together is the fact that both the B cell and T cell arms of the adaptive immune response are affected. Children with this disease usually die of opportunistic infections within their first year of life unless they receive a bone marrow transplant. Such a procedure had not yet been perfected for David Vetter, the “boy in the bubble,” who was treated for SCID by having to live almost his entire life in a sterile plastic cocoon for the 12 years before his death from infection in 1984. One of the features that make bone marrow transplants work as well as they do is the proliferative capability of hematopoietic stem cells of the bone marrow. Only a small amount of bone marrow from a healthy donor is given intravenously to the recipient. It finds its own way to the bone where it populates it, eventually reconstituting the patient’s immune system, which is usually destroyed beforehand by treatment with radiation or chemotherapeutic drugs. New treatments for SCID using gene therapy, inserting nondefective genes into cells taken from the patient and giving them back, have the advantage of not needing the tissue match required for standard transplants. Although not a standard treatment, this approach holds promise, especially for those in whom standard bone marrow transplantation has failed.

What phase does dna replication occur in the cell cycle?

Mitosis

Gap 0

apoptosis

synthesis

DNA replication occurs during the S phase (the Synthesis phase) of the cell cycle, before mitosis and cell division. The base pairing rules are crucial for the process of replication. DNA replication occurs when DNA is copied to form an identical molecule of DNA.

What type of rocks form when magma cools and forms crystals?

seismic

sedimentary

metarmorphic

igneous

Igneous rocks form when magma cools and forms crystals. These rocks can form at Earth’s surface or deep underground. Figure below shows a landscape in California’s Sierra Nevada that consists entirely of granite.

What determines the color of a star?

age of the star

size of the star

core temperature

surface temperature

The color of a star is determined by its surface temperature.

Why do birds build nests?

hatch eggs

get off ground

raise birds

safe place

Birds and wasps build nests to have a safe place to store their eggs and raise their young. Many other animals build nests for the same reason. Animals protect their young in other ways, as well. For example, a mother dog not only nurses her puppies. She also washes them with her tongue and protects them from strange people or other animals. All of these behaviors help the young survive and grow up to be adults.

Flagella, cilia and pseudopods are appendages that protists use for what purpose?

momentum

gravity

pressure

movement

Most protists have motility . This is the ability to move. Protists have three types of appendages for movement. As shown in Figure below , they may have flagella, cilia , or pseudopods (“false feet”). There may be one or more whip-like flagella. Cilia are similar to flagella, except they are shorter and there are more of them. They may completely cover the surface of the protist cell. Pseudopods are temporary, foot-like extensions of the cytoplasm.

Another interesting phenomenon associated with polarized light is the ability of some crystals to split an unpolarized beam of light into two. such crystals are said to be this?

opaque matter

reflective

phosphorescent

birefringent

Another interesting phenomenon associated with polarized light is the ability of some crystals to split an unpolarized beam of light into two. Such crystals are said to be birefringent (see Figure 27.50). Each of the separated rays has a specific polarization. One behaves normally and is called the ordinary ray, whereas the other does not obey Snell’s law and is called the extraordinary ray. Birefringent crystals can be used to produce polarized beams from unpolarized light. Some birefringent materials preferentially absorb one of the polarizations. These materials are called dichroic and can produce polarization by this preferential absorption. This is fundamentally how polarizing filters and other polarizers work. The interested reader is invited to further pursue the numerous properties of materials related to polarization.

A mitotic spindle forms from the what?

ribosomes

sister chromatids

centrioles

centrosomes

A mitotic spindle forms from the centrosomes. The nuclear envelope dissolves. Chromosomes attach to the mitotic spindle, which separates the chromosomes and elongates the cell.

What is the transfer of thermal energy between objects that have different temperatures?

sweat

humidity

warm

heat

Heat is the transfer of thermal energy between objects that have different temperatures. Thermal energy always moves from an object with a higher temperature to an object with a lower temperature. Specific heat is the amount of energy (in joules) needed to raise the temperature of 1 gram of a substance by 1°C. Substances differ in their specific heat.

What is the process in which cells make proteins called?

respiration

catalysis

apoptosis

synthesis

The process in which cells make proteins is called protein synthesis . It actually consists of two processes: transcription and translation. Transcription takes place in the nucleus. It uses DNA as a template to make an RNA molecule. RNA then leaves the nucleus and goes to a ribosome in the cytoplasm, where translation occurs. Translation reads the genetic code in mRNA and makes a protein.

Living things on the ocean floor are known as?

newts

decomposers

protozoa

benthos

Benthos are living things on the ocean floor. Many benthic organisms attach themselves to rocks and stay in one place. This protects them from crashing waves and other water movements. Some benthic organisms burrow into sediments for food or protection. Benthic animals may crawl over the ocean floor. Examples of benthos include clams and worms. Figure below shows two other examples.

A double form of what reproductive process is unique to angiosperms?

infection

stimulation

destruction

fertilization

Figure 14.26 This diagram shows the lifecycle of an angiosperm. Anthers and ovaries are structures that shelter the actual gametophytes: the pollen grain and embryo sac. Double fertilization is a process unique to angiosperms. (credit: modification of work by Mariana Ruiz Villareal).

What is the term for the conversion of a liquid to its vapor below the boiling temperature of the liquid?

oxidation

absorption

vaporization

evaporation

Evaporation is the conversion of a liquid to its vapor below the boiling temperature of the liquid.

What kind of energy conversion is done by a fuel cell?

electrical into nuclear

wind into nuclear

solar into chemical

chemical into electrical

Fuel Cells A fuel cell is a device that converts chemical energy into electrical energy. Fuel cells are similar to batteries but require a continuous source of fuel, often hydrogen. They will continue to produce electricity as long as fuel is available. Hydrogen fuel cells have been used to supply power for satellites, space capsules, automobiles, boats, and submarines (Figure 17.15).

In which aspect does molality differ from molarity?

complexity

numerator

accuracy

denominator

Molality differs from molarity only in the denominator. While molarity is based on the liters of solution, molality is based on the kilograms of solvent. Concentrations expressed in molality are used when studying properties of solutions related to vapor pressure and temperature changes. Molality is used because its value does not change with changes in temperature. The volume of a solution, on the other hand, is slightly dependent upon temperature.

What is the mass that is "lost" in fission or fusion actually converted to?

hydrogen

momentum

pressure

energy

When the nucleus of a radioisotope undergoes fission or fusion, it loses a tiny amount of mass. What happens to the lost mass? It isn’t really lost at all. It is converted to energy. How much energy? . The change in mass is tiny, but it results in a great deal of energy.

What does a glacier leave behind when it retreats?

sediment

Dirt

Lakes

bare rock

a glacier retreats and leaves behind bare rock.

What law states that matter cannot be created or destroyed even when it changes?

modification of mass

Action of mass

Transfer of mass

conservation of mass

Matter cannot be created or destroyed even when it changes. This is the law of conservation of mass.

What are natural sponges made of?

sea shells

sand

sea plants

sea animals

Natural sponges, like the one in the picture above, are actually animals taken from the sea! The sponges in your home, however, were most likely never living things. Most sponges used in kitchens today are made from unnatural materials.

The process in which certain bacteria change nitrogen gas to a form that plants can absorb through their roots is known as what?

dioxide fixation

pollen fixation

oxygen fixation

nitrogen fixation

Even though nitrogen gas makes up most of Earth's atmosphere, plants cannot use this nitrogen gas to make organic compounds for themselves and other organisms. The two nitrogen atoms in a molecule of nitrogen gas are held together by a very stable triple bond. This bond must be broken for the nitrogen to be used. The nitrogen gas must be changed to a form called nitrates, which plants can absorb through their roots. The process of changing nitrogen gas to nitrates is called nitrogen fixation . It is carried out by nitrogen-fixing bacteria. The bacteria live in soil and roots of legumes, such as peas.

What gas is actually a waste product of photosynthesis?

nitrogen

carbon dioxide

hydrogen

oxygen

Around 3 billion years ago, photosynthesis began. Organisms could make their own food from sunlight and inorganic molecules. From these ingredients they made chemical energy that they used. Oxygen is a waste product of photosynthesis. That first oxygen combined with iron to create iron oxide. Later on, the oxygen entered the atmosphere.

Distinguished by the great red spot, what planet has an upper atmosphere containing ammonia clouds?

mars

saturn

uranus

jupiter

Jupiter's atmosphere is unlike any other in the solar system! The upper layer contains clouds of ammonia. The ammonia is different colored bands. These bands rotate around the planet. The ammonia also swirls around in tremendous storms. The Great Red Spot ( Figure below ) is Jupiter's most noticeable feature. The spot is an enormous, oval-shaped storm. It is more than three times as wide as Earth! Clouds in the storm rotate counterclockwise. They make one complete turn every six days or so. The Great Red Spot has been on Jupiter for at least 300 years. It may have been observed as early as 1664. It is possible that this storm is a permanent feature on Jupiter. No one knows for sure.

What controls what goes in and out of a cell?

the mitochondria

the cilia

the nucleus

the plasma membrane

The function of the plasma membrane is to control what goes in and out of the cell. Some molecules can go through the cell membrane to enter and leave the cell, but some cannot. The cell is therefore not completely permeable. "Permeable" means that anything can cross a barrier. An open door is completely permeable to anything that wants to enter or exit through the door. The plasma membrane is semipermeable , meaning that some things can enter the cell, and some things cannot.

If the average binding energy per nucleon overcomes the repulsion, the nucleus stays together and it referred to as what?

closed

even

solid

stable

Each nucleus, therefore, has competing forces. The repulsive force between the protons tends to blow the nucleus apart and the binding energy tends to hold the nucleus together. If the average binding energy per nucleon overcomes the repulsion, the nucleus stays together and it referred to as stable. If the repulsion overcomes the average binding energy per nucleon, the nucleus may blow apart or undergo nuclear disintegration . When a nucleus disintegrates, it throws off pieces of itself and energy in the form of gamma rays . This disintegration process came to be called radioactivity .

What is mollusks complete digestive system called?

thallus

choroid

vesicle

coelom

Mollusks also have a coelom, a complete digestive system, and specialized organs for excretion.

Kinetic energy is the energy of what?

wind

heat

light

motion

Kinetic energy is the energy of motion.

Which area in a lake is likely to have more nutrients?

surface

crust

reef

bottom

Water near the bottom of lakes and the ocean may contain more nutrients than water closer to the surface. When aquatic organisms die, they sink to the bottom. Decomposers near the bottom of the water break down the dead organisms and release their nutrients back into the water.

Temperature is a measure of how hot or cold an object is relative to another object, whereas heat is the flow of what energy between objects with different temperatures?

potential energy

nuclear energy

gravitational energy

thermal energy

Temperature The concept of temperature may seem familiar to you, but many people confuse temperature with heat. Temperature is a measure of how hot or cold an object is relative to another object (its thermal energy content), whereas heat is the flow of thermal energy between objects with different temperatures. Three different scales are commonly used to measure temperature: Fahrenheit (expressed as °F), Celsius (°C), and Kelvin (K). Thermometers measure temperature by using materials that expand or contract when heated or cooled. Mercury or alcohol thermometers, for example, have a reservoir of liquid that expands when heated and contracts when cooled, so the liquid column lengthens or shortens as the temperature of the liquid changes.

Scientists use seismographs and intersecting circles to determine the location of what?

volcano

tsunami

hurricane

earthquake epicenter

Next, the seismologists try to determine the location of the earthquake epicenter. To do this they need the distances to the epicenter from at least three seismographs. Let’s say that they know that an earthquake’s epicenter is 50 kilometers from Kansas City. They draw a circle with a 50 km radius around that seismic station. They do this twice more around two different seismic stations. The three circles intersect at a single point. This is the earthquake’s epicenter ( Figure below ).

What happens when iron is exposed to water and oxygen?

combustion

smoking

shrinking

rusting

Corrosion involves the formation of an oxidized form of a metal by an electrochemical process. A common example is the rusting of iron when exposed to water and oxygen. The tarnishing of silver and the red or green deposits formed on copper are other examples. Corrosion in all its forms costs the U. S. millions of dollars each year in expenses for metal replacement.

What disease is generally caused by mutations in genes that regulate the cell cycle?

pneumonia

heart disease

arthritis

cancer

Cancer is a disease in which cells grow out of control and form abnormal masses of cells. It is generally caused by mutations in genes that regulate the cell cycle. Because of the mutations, cells with damaged DNA are allowed to divide without limits. Cancer causing genes can be inherited. You can learn more about hereditary cancer by watching the video at the following link: http://www. youtube. com/watch?v=LWk5FplsKwM (4:29).

Proteins are organic compounds made up of what type of acids?

lactic

nucleic

enzyme

amino

Proteins are organic compounds made up of amino acids. They form muscles, speed up chemical reactions, and perform many other cellular functions.

Speciation is usually due to a single instance of what?

radiation

division

accumulation

mutation

null

What is the name of the extra layer that prokaryotes have outside the cell wall?

a shell

a bone

a shape

a capsule

Many prokaryotes have an extra layer, called a capsule, outside the cell wall. The capsule protects the cell from chemicals and from drying out. It also allows the cell to stick to surfaces and to other cells. Because of this, many prokaryotes can form biofilms, like the one shown in Figure below . A biofilm is a colony of prokaryotes that is stuck to a surface such as a rock or a host’s tissues. The sticky plaque that collects on your teeth between brushings is a biofilm. It consists of millions of bacteria.

The binary halides are an important subclass of what?

gases

acids

minerals

salts

Halides of the Representative Metals Thousands of salts of the representative metals have been prepared. The binary halides are an important subclass of salts. A salt is an ionic compound composed of cations and anions, other than hydroxide or oxide ions. In general, it is possible to prepare these salts from the metals or from oxides, hydroxides, or carbonates. We will illustrate the general types of reactions for preparing salts through reactions used to prepare binary halides. The binary compounds of a metal with the halogens are the halides. Most binary halides are ionic. However, mercury, the elements of group 13 with oxidation states of 3+, tin(IV), and lead(IV) form covalent binary halides. The direct reaction of a metal and a halogen produce the halide of the metal. Examples of these oxidation-reduction reactions include: Cd(s) + Cl 2(g) ⟶ CdCl 2(s) 2Ga(l) + 3Br 2(l) ⟶ 2GaBr 3(s).

When was construction of the hoover dam completed?

1905

1959

1969

1935

If you take a trip out of Las Vegas toward Phoenix you can visit the Hoover Dam. Completed in 1935, the dam provides power to over a million homes. It also stores water for use by the residents of the desert southwest. Hoover Dam is one of the engineering marvels of the 20th century.

Some plants can produce seeds without fertilization and this method of reproduction is known as what?

Density

gametes

amoebas

apomixis

Some plants can produce seeds without fertilization. Either the ovule or part of the ovary, which is diploid in nature, gives rise to a new seed. This method of reproduction is known as apomixis. An advantage of asexual reproduction is that the resulting plant will reach maturity faster. Since the new plant is arising from an adult plant or plant parts, it will also be sturdier than a seedling. Asexual reproduction can take place by natural or artificial (assisted by humans) means.

What type of chains do unsaturated fatty acids have?

Broken Chains

Spiral Chains

Stait Chains

bent chains

Fatty Acids. Saturated fatty acids have straight chains, like the three fatty acids shown in the upper left. Unsaturated fatty acids have bent chains, like all the other fatty acids in the figure.

Ribosomes are the site of what process?

Measure Synthesis

organism synthesis

consume synthesis

protein synthesis

8.5 Ribosomes Ribosomes are the site of protein synthesis. Ribosomes themselves are synthesized in the cell nucleoli28 and are structured as two subunits, the large and the small. These parts are composed of RNA and protein. Prokaryotic and eukaryotic ribosomes are different, the eukaryotic ones being larger and more complicated.

Bacteria and archaea that survive under extreme conditions are called?

carotenoids

audiophiles

rotifers

extremophiles

phototrophs and began the oxygenation of the atmosphere. The increase in oxygen concentration allowed the evolution of other life forms. Fossilized microbial mats are called stromatolites and consist of laminated organo-sedimentary structures formed by precipitation of minerals by prokaryotes. They represent the earliest fossil record of life on Earth. Bacteria and archaea grow in virtually every environment. Those that survive under extreme conditions are called extremophiles (extreme lovers). Some prokaryotes cannot grow in a laboratory setting, but they are not dead. They are in the viable-but-non-culturable (VBNC) state. The VBNC state occurs when prokaryotes enter a dormant state in response to environmental stressors. Most prokaryotes are social and prefer to live in communities where interactions take place. A biofilm is a microbial community held together in a gummy-textured matrix.

The production and transport of gametes is performed by what type of organs?

digestion

degradation

skin

reproductive

46.3 Reproductive organs produce and transport gametes.

What are atoms of the same element but with different numbers of neutrons called?

electrons

variations

masses

isotopes

Isotopes are atoms of the same element but with different numbers of neutrons.

Active transport mechanisms require the use of the cell’s energy, usually in the form of what?

protein

ribonucleic acid (RNA)

deoxyribonucleic acid (DNA)

adenosine triphosphate (atp

3.6 | Active Transport By the end of this section, you will be able to: • Understand how electrochemical gradients affect ions • Describe endocytosis, including phagocytosis, pinocytosis, and receptor-mediated endocytosis • Understand the process of exocytosis Active transport mechanisms require the use of the cell’s energy, usually in the form of adenosine triphosphate (ATP). If a substance must move into the cell against its concentration gradient, that is, if the concentration of the substance inside the cell must be greater than its concentration in the extracellular fluid, the cell must use energy to move the substance. Some active transport mechanisms move small-molecular weight material, such as ions, through the membrane. In addition to moving small ions and molecules through the membrane, cells also need to remove and take in larger molecules and particles. Some cells are even capable of engulfing entire unicellular microorganisms. You might have correctly hypothesized that the uptake and release of large particles by the cell requires energy. A large particle, however, cannot pass through the membrane, even with energy supplied by the cell.

What kind of energy can move through glass much better than through paper?

heat

vibrational

sound

light

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What forms when one substance dissolves into another?

solvent

mixture

compound

solution

When one substance dissolves into another, a solution is formed. A solution is a homogeneous mixture consisting of a solute dissolved into a solvent . The solute is the substance that is being dissolved, while the solvent is the dissolving medium. Solutions can be formed with many different types and forms of solutes and solvents.

What transition occurs as heat is added or removed from a substance?

heat wave

thermal reaction

diffusion transition

phase transition

Phase transitions occur as heat is added or removed from a substance.

What is the predicted year that as many as half of all remaining species could go extinct?

2020

3000

2040

2050

Evidence shows that a sixth mass extinction is happening right now. Species are currently going extinct at the fastest rate since the dinosaurs died out. Dozens of species are going extinct every day. If this rate continues, as many as half of all remaining species could go extinct by 2050.