Ecology (BIOL 3130) Study Quiz Answers Exam 1
What is the average percentage of usable energy that is transferred to the next trophic level when organisms are consumed by other organisms? A. <5% B. 5-10% C. 10-15% D. 15-20% E. 20-25%
B. 5-10%
As defined in this class, there are no environments on the moon. A. True B. False
A. True We defined the environment to be an organism's surroundings. Since there are no living organisms on the moon, there are no environments.
What is the term used to represent the non-living component of an ecosystem? A. Abiotic B. Detritus C. Efferent D. Geohydrolic E. Inanimate
A. abiotic
Which of the following is an example of a primary carnivore? A. A crow that eats portions of the carcass left behind by a secondary carnivore B. A hawk that eats granivorous birds C. A mountain lion which is the top predator in its ecosystem and eats everything D. A snake that eats insectivorous lizards E. None of these are primary carnivores.
B. A hawk that eats granivorous birds A primary carnivore eats herbivores, and granivorous birds are herbivores. The crow would be a secondary carnivore (and scavenger) because the carcass would have to be a primary carnivore. The mountain lion would not really fit in this terminology because it would eat herbivores, primary consumers, secondary carnivores, etc. The snake would be at least a secondary carnivore depending upon what the insects are that were eaten by the lizards.
Which of the following statements is not true about autotrophs? A. Autotrophs are able to produce their own food. B. Autotrophs use simple inorganic substances as a food resource. C. Most autotrophs produce food through photosynthesis. D. Most autotrophs generate O2 when producing food. E. Autotrophs provide food to heterotrophs that consume them.
B. Autotrophs use simple inorganic substances as food resources. CO2 is not the food resource; sugars and starches are the food used by the autotrophs when they respire.
Which of the following is not a correct term for the study of a single species of salamander in which it was determined where and why it occurred at certain locations, what it ate, how many eggs it laid, and other such information? A. Ecology B. Field Biology C. Natural History D. Synecology E. All of these terms are correct.
D. Synecology Since a single species was being studied, this is an autecology study (not synecology).
Which of the following terms is incorrect when referring to a Canada goose which feeds almost entirely on living blades of grass? A. Consumer B. Folivore C. Herbivore D. Heterotroph E. Scavenger
E. Scavenger Scavengers eat dead or rotting plants or animals.
Which of the following statements is not true about biomes? A. Biomes are the most easily recognized subdivision of the biosphere. B. Temperature and/or rainfall are important factors influencing the presence of most biomes. C. Biomes consist of a single, very large ecosystem. D. Although animals and plants differ in different parts of the world, they often are ecologically similar if from the same biome, but on different continents. E. Some biomes are not found in the U.S but occur elsewhere in the world.
The correct (i.e., false) answer is C. Biomes consist of several different ecosystems that are similar and related to each other.
Which of the following statements is not true concerning food chains and food webs? A. A food chain represents one of several pathways of energy and material flow in a food web. B. Energy decreases at higher trophic levels in food chains. C. Individual organisms often occur at a different trophic level in different food chains within a food web. D. Diversity of species increases at higher trophic levels in food chains. E. Computer simulations can be used to illustrate the importance of various food chains within food webs.
The correct answer (i.e., false statement) is D. At higher trophic levels, there are fewer types of species because of lower amounts of energy and nutrients available. The other answers are all true. Answer A is another way of saying that food webs are all of the food chains in a community hooked together. Answer B is repeatedly stated throughout this presentation. Answer C is illustrated by the bear in bullet two of slide 9; it is in the 2nd trophic level when it eats acorns, the 3rd tropic level when it eats herbivores, and at least the 4th trophic level when it eats carnivores. Answer E is a synthesis of bullets three and four in slide 9. Using the bear as an example, if it eats far more acorns than insects, more energy will flow through the "acorn" food chain than the "insect" food chain. Tracing the amount of energy in various food chains is best accomplished with computer simulations.
Which of the following statements is not true concerning assimilation efficiency in animals? A. In general, herbivores have a lower assimilation efficiency than carnivores. B. Some herbivores have a higher assimilation efficiency than some carnivores. C. Fruit is generally easier to digest than grass because of the high cellulose content in grass. D. Meat is generally easier to digest than insects because insects have chitinous exoskeletons. E. Wood eaters (e.g., beavers) have special adaptations that enable them to have high assimilation efficiencies.
The correct answer (i.e., false statement) is E. Although it is true that beavers and other wood eaters have special adaptations that enable them to acquire some energy from wood, it is still among the lowest assimilation efficiency of any of the herbivores. If we ate wood, we would not get any energy from it because we don't have the digestive enzymes to break it down.
Tissue of parasitic plants that derive all of their energy from the roots of host plants is a type of secondary production. A. True B. False
The correct answer is A (True) because such parasitic plants are unable to photosynthesize and are consequently heterotrophs. Some parasitic plants (e.g., some mistletoes) photosynthesize and only get water and nutrients from the host plants. They are autotrophs, and their tissue would be considered NPP. Some hemiparasitic plants derive part of their energy from their hosts and part by photosynthesis; such species would be involved in both primary and secondary production.
The trophic level of a fox that eats only birds cannot be determined without additional information. A. True B. False
The correct answer is A (True) because the trophic level of the bird is unknown because we don't know what it eats. Foxes that only eat granivorous birds belong to the 3rd trophic level. However, foxes that eat birds that eat other birds (e.g., hawks) belong to at least the 4th trophic level (and perhaps higher).
Carnivores in a population with a low utilization efficiency are generally in better body condition than animals of the same species in a population with a high utilization efficiency. A. True B. False
The correct answer is A (True). Animals that are eating a high percentage of their prey base are generally in poorer condition than those in populations where food is plentiful. If they over exploit their prey base, mortality increases and reproduction declines. This is one efficiency ratio where less can be better than more.
Where does most of the woody tissue come from in a tree? A. Air and Water B. Water and Soil C. Soil and Sun D. Sun and Water E. None of the above
The correct answer is A because water and CO2 in the atmosphere are converted to glucose, that in turn is converted to complex organic compounds (i.e., wood). This relationship is driven by photosynthesis and the sun, but the actual carbon comes from CO2, and hydrogen comes from water (oxygen comes from both). Carbon sequestration is being advocated to combat global climate change by using tree growth to reduce carbon in the atmosphere.
In which of the following biomes is fire a major environmental factor? A. Chaparral B. Desert C. Grasslands D. Northern Coniferous Forest E. Temperate Deciduous Forest
The correct answer is A.
Which of the following elements is not required by most living organisms? A. Argon B. Boron C. Cobalt D. Fluorine E. Molybdenum
The correct answer is A. Argon is a noble gas that is inert and not used by living organisms. The other four answers were all listed in the presentation as elements needed in very small amounts by most organisms.
What is the correct term for an earthworm which consumes leaf material that is partially decomposed? A. Detritivore B. Omnivore C. Saprophyte D. Scavenger E. None of the above
The correct answer is A. Partially decomposed leaf material is called detritus, and animals that consume it are detritivores.
If the Ecological Growth Efficiency is 20% and the Utilization Efficiency is 40%, what is the Ecological Efficiency? A. Less than 10% B. 10% C. 20% D. 30% E. Greater than 30%
The correct answer is A. The Ecological Efficiency can be derived by multiplying the other two efficiency ratios together (0.2 times 0.4 equals 0.08 or 8%).
Some portions of the earth are not included within the biosphere. A. True B. False
The correct answer is A. There is no life on some portions of the earth (e.g., deep within the core), and these areas are not part of the biosphere. Essentially, life occurs everywhere on the surface of the earth and throughout the oceans, so only the core and the outer atmosphere are not included in the biosphere.
As defined in this class, which of the following terms is not correct when studying the interaction of 12 species of invertebrates living in a tidal pool (e.g., mussels, sea urchins, snails, and starfish)? A. Aquatic Ecology B. Community Ecology C. Field Biology D. Synecology E. All of these are correct terms for this type of study.
The correct answer is A. We defined aquatic ecology as the study of freshwater environments, and this would be a marine biology study.
Bioextraction and bioremediation are synonymous terms for the same process. A. True B. False
The correct answer is B (False). Bioextraction refers to removing living organisms from an ecosystem after they have accumulated undesirable nutrients (e.g., excess phosphorus and nitrogen accumulated by Ribbed Mussels). Bioremediation refers to using living organisms to change a nutrient from an undesirable form to a more desirable form (e.g., using purple sulfur bacteria to transform hydrogen sulfide into pure sulfur).
The U.S. now has an excellent system to evaluate the potential long-term effects of synthetic chemicals, and it is unlikely that another problem like DDT will occur again. A. True B. False
The correct answer is B (False). Most of our testing of synthetic chemicals is of immediate dangers and not long-term effects. Consequently, problems arise almost every year, and chemicals are commonly banned that were considered to be safe a few years before. The example of Endocrine Disruptor Chemicals was used to illustrate this problem in the presentation.
Nitrification and denitrification are opposite processes within the nitrogen cycle. A. True B. False
The correct answer is B (False). Nitrification is a two-step process that converts ammonium in the soil or water into nitrite and then nitrate. Denitrification converts nitrates into gaseous nitrogen that is released into the atmosphere.
Nitrogen fixing bacteria convert atmospheric nitrogen into a form that is readily absorbed by plants through their roots. A. True B. False
The correct answer is B (False). Nitrogen fixing bacteria convert atmospheric nitrogen into ammonium ions. However, ammonium ions are not readily absorbed by plants, and nitrifying organisms are needed to convert ammonium into nitrites and nitrates which are readily absorbed.
What is the difference between Gross Primary Production (GPP) and Net Primary Production (NPP)? A. GPP is energy fixed by autotrophs, whereas NPP is fixed by heterotrophs. B. NPP accounts for the energy used by autotrophs to drive cellular processes; GPP does not. C. GPP is the energy that is available for the next trophic level. D. NPP is always greater than GPP. E. There is no difference; they are different terms for the same concept.
The correct answer is B because NPP = GPP - R.
When a snake eats a mouse, some of the energy that it consumes is lost in feces and some is lost in urine. What is the remaining energy called? A. Assimilation Energy B. Metabolizable Energy C. Ingested Energy D. Primary Production E. Secondary Production
The correct answer is B, Metabolizable Energy. It is also called Available Energy.
9. The ultimate sources of energy in all biological ecosystems is solar energy (i.e., the sun). A. True B. false
The correct answer is B. Although the sun is the source of energy in most ecosystems, a few organisms can trap energy by chemosynthesis in the absence of sunlight. For example, organisms near deep sea vents are dependent upon bacteria that convert sulfur and methane into organic molecules on which other organisms feed.
In the diagram on slide 3, it shows the mouse as belonging to trophic level 3. For this to be true, what is the mouse eating? A. Grass B. Grasshoppers C. Snakes D. Purina Mouse Chow E. It doesn't matter what it eats; it belongs to trophic level 3.
The correct answer is B. An animal in trophic level 3 is a carnivore that eats herbivores. Therefore, it must be eating grasshoppers, which are the herbivores in the diagram. Although rabbits would have been a correct answer, as well; I don't know of many mice that can eat a rabbit.
Which of the following statements is true about parasites? A. Most parasites kill their hosts after a brief period of heavy infestation. B. Some parasites do not feed on the tissue of their hosts. C. Plants that parasitize animals are more common than animals that parasitize plants. D. Parasites generally display very few adaptations because most of them are generalists. E. Very few parasites are host specific.
The correct answer is B. Many parasites (e.g., tapeworms) attach to their hosts intestines and "steal" food that is passing through the animal's body before it is absorbed by the host.
What is the primary food of herbivorous mammals that live in the Tropical Savanna? A. Tree bark B. Grass blades C. Fruits and nuts D. Mosses and lichens E. Leaves of deciduous trees
The correct answer is B. Savannas are grasslands with scattered trees, and the most abundant food resource for herbivorous mammals is grass blades. As a result, the number and diversity of such species is greater in Tropical Savannas of Africa than anywhere else in the world.
What are we referring to when we say that only a small amount of energy is passed on from one trophic level to the next? A. Assimilation Efficiency B. Ecological Efficiency C. Exploitation Efficiency D. Gross Production Efficiency E. Utilization Efficiency
The correct answer is B. The energy to which we refer is the amount of energy at any one point in time. This would be Net Primary Production in the case of autotrophs and Secondary Production in the case of heterotrophs. The Ecological Efficiency divides this amount at one trophic by the amount at the previous trophic level. This is the reason that it is also called Food Chain Efficiency. Note: For herbivores, the formula would be Secondary Production (N) / Net Primary Production (N-1).
Which of the following nutrients does not occur most commonly in rocks? A. Carbon B. Nitrogen C. Phosphorous D. Sulfur E. All of these occur most commonly in rocks.
The correct answer is B. The largest reservoir of Nitrogen is the atmosphere. The largest reservoir of Carbon, Phosphorous, and Sulfur are rock formations.
Which of the following processes results in surface water moving into a groundwater reservoir? A. Evaporation B. Percolation C. Precipitation D. Sublimation E. Transpiration
The correct answer is B. Water percolates through the soil to contribute to groundwater. To answer this question, you should look at the picture on slide 7 and list of processes on slide 8. Evaporation, sublimation, and transpiration are all processes that transfer water into the atmosphere. Precipitation returns water from the atmosphere.
If you cut all of the grass in a lawn one time, dry it in a drying oven, and measure the energy content by burning the material in a calorimeter, what have you determined? A. Gross Primary Productivity B. Net Primary Production C. Secondary Productivity D. Gross Primary Production E. Net Primary Productivity
The correct answer is B. You did not account for plant respiration, so it cannot be gross primary production or productivity, and secondary productivity relates to heterotrophs, not plants in a field. Since you only sampled once, you could not determine the rate of biomass accumulation because you do not know how long it took for the grass to grow to the level when cut, so it would be production and not productivity.
Which of the following methods used to measure primary productivity does not rely on changes in gas exchange during photosynthesis? A. Carbon Dioxide Assimilation Method B. Carbon-14 Method C. Chlorophyll Method D. Light Dark Bottle Method E. Modified Oxygen Liberation Method
The correct answer is C where chlorophyll content is measured and assumed to be directly related to energy productivity. The first two methods measure CO2 used during photosynthesis, and the last two methods measure O2 released during photosynthesis.
What are the two primary factors that determine what biome occurs at a specific location? A. Soil Type and Frequency of Disturbance B. Frequency of Disturbance and Climate C. Climate and Geography D. Geography and Plant Community E. Plant Community and Soil Type
The correct answer is C.
Which of the following animals is paired incorrectly with a major biome in which it occurs? A. Caribou - Tundra B. Kangaroo Rat - Desert C. Moose - Moist Temperate Coniferous Forest D. Pronghorn - Grasslands E. Wild Turkey - Temperate Deciduous Forest
The correct answer is C. Moose are most abundant in the Northern Coniferous Forest and do not occur in the Moist Temperate Coniferous Forest.
Which of the following statements is true concerning the six most important elements making up the body mass of most living organisms? A. Carbon is the most abundant element in living organisms. B. Hydrogen occurs most commonly in the atmosphere. C. Phosphorus is the most likely element of the six to become limiting over the next 100 years. D. Potassium is one of the six most abundant elements in living organisms. E. Sulfur is a critical component of DNA, RNA, and ATP.
The correct answer is C. Most Phosphorus fertilizer comes from mining Phosphate rocks, and reserves are expected to be depleted in 50-100 years, with some projections being even sooner. As for the other answers, Oxygen is the most abundant element in living organisms, Hydrogen mostly occurs in water, Potassium is an important element but not one of the top six, and Phosphorus is the element that is a component of DNA, RNA, and ATP.
Which of the following statements is not true about various biomes of the world? A. Precipitation is light in the Tundra, but soils are often waterlogged. B. Tropical Savannas are often maintained by periodic disturbance that keeps them from becoming forests. C. Precipitation is heavy in Northern Coniferous Forest, but soils are well drained and fertile. D. Tropical Rain Forest diversity of plants and animals is extremely high despite the soils being relatively infertile. E. Precipitation is light on Grasslands, and soils are often fertile.
The correct answer is C. Precipitation in the Northern Coniferous Forest is moderate, more than the Tundra, but less than the Temperate Deciduous Forest. Soils are generally wet and boggy because of the long, cold winters and generally infertile, partially because of low decomposition rates.
Which of the following terms is correct for a snake that eats only eggs? A. Avivore B. Autotroph C. Carnivore D. Omnivore E. None of the above
The correct answer is C. Such a snake is an Ovivore, which is a type of Carnivore.
Based on this presentation, as well as slides 18 and 20 of the second presentation (Ecosystems) which of the following statements is true? A. Primary carnivores are primary consumers. B. The first trophic level consists of herbivores. C. Tertiary carnivores belong to the 5th tropic level. D. Tertiary carnivores are always larger and more aggressive than omnivores. E. All of these statements are true.
The correct answer is C. Tertiary carnivores eat secondary carnivores (trophic level 4). The following explains why the other answers are false. Primary carnivores eat herbivores and are secondary consumers. The first trophic level consists of autotrophs. A fox or hawk that eats snakes would be a tertiary carnivore, and foxes and hawks are far smaller and less aggressive than grizzly bears which are depicted in slide 20. Only one statement is correct, so statement E is false.
What is the correct term for an animal that eats entirely plants during the winter but animals during the summer? A. Carnivore B. Herbivore C. Omnivore D. Saprophyte E. None of the above
The correct answer is C. This type of omnivore is sometimes referred to as seasonal herbivores and seasonal carnivores.
Which of the following nutrients is least often associated with fossil fuels? A. Carbon B. Hydrogen C. Nitrogen D. Phosphorus E. Sulfur
The correct answer is D (Phosphorus). Carbon, Nitrogen, and Sulfur have gaseous forms that are released into the atmosphere when fossil fuels are burned. Hydrogen fuel has promise as a zero-emission fuel, but most of it is produced by steam reforming of fossil fuels, resulting in carbon emissions.
Which of the following statements is true about biotic pyramids? A. Biotic pyramids are based on individual food chains and not on food webs. B. There are two types of biotic pyramids - energy and biomass. C. Biomass pyramids are never inverted, but energy pyramids are inverted on rare occasions. D. An inverted pyramid is not entirely inverted; only one trophic level needs to be smaller than expected to be considered inverted. E. All of these statements are true.
The correct answer is D, as illustrated by slide 15. Biotic pyramids are actually based on food webs because each level represents all organisms within that trophic level. There are three types of biotic pyramids - numbers, as well as energy and biomass. Biomass pyramids can be inverted, but energy pyramids cannot be inverted.
In which of the following biomes do the largest trees occur? A. Tropical Rain Forest B. Northern Coniferous Forest C. Temperate Deciduous Forest D. Moist Temperate Coniferous Forest E. Tropical Savanna
The correct answer is D, sometimes called the Temperate Rain Forest. All of the trees listed on the slide are among the largest trees on earth, including Redwood which is the tallest tree on earth. The largest tree by mass is the Giant Sequoia that occurs in the Sierra Nevada Mountains of eastern California. The Sierras are treated differently in different biome systems, sometimes being lumped with Moist Temperate Coniferous Forest and sometimes placed within a separate Mountain Biome.
Which of the following statements is not true about energy flow and nutrient cycling? A. All life on earth is dependent upon energy flow and nutrient cycling. B. Energy flow and nutrient cycling occur together in ecosystems. C. Energy flow and nutrient cycling involve both the living and non-living components of the ecosystem. D. Energy and nutrients recirculate in the ecosystem. E. Efficiency of energy flow and nutrient cycling influence community complexity.
The correct answer is D. Although nutrients recirculate in an ecosystem, energy flow is one -way (i.e., usable energy is lost as it flows through a community), and additional solar energy is needed to keep the ecosystem functioning. If the sun were to die, most life on earth would cease to exist.
Which of the following biomes has been least altered by human development in North America? A. Chaparral B. Grasslands C. Moist Temperate Coniferous Forest D. Northern Coniferous Forest E. Temperate Deciduous Forest
The correct answer is D. Currently about 80% of the Northern Coniferous Forest is still intact and unaltered, but logging is considered a future threat. The other biomes on this list have been highly altered in North America. Chaparral has been altered for urban development, and much of the Grasslands have been converted to farmland. Logging, followed by urban development and conversion to farmland, has been extensive in the Moist Temperate Coniferous Forest and even more so in the Temperate Deciduous Forest.
Which of the following cycles does not involve a significant atmospheric component? A. Carbon Cycle B. Hydrogen Cycle C. Nitrogen Cycle D. Phosphorus Cycle E. Sulfur Cycle
The correct answer is D. Most forms of Phosphorous occur in rock formations, soils, water, and living organisms. The other four have various gaseous forms that are found in the atmosphere, at least in small amounts.
Which of the following ecosystems is the least productive? A. Agricultural Field B. Grassland C. Lake D. Open Ocean E. Swamp
The correct answer is D. Open oceans comprise over 70% of the surface of the earth, with the other ~10% of least productive habitat being deserts. Although the figures provided in slide 25 were actually biomass accumulation figures, a rough energy estimate can be derived by using the conversion factor on slide 23.
Which of the following statements is true concerning oxygen? A. Oxygen is the most abundant gas in the atmosphere. B. Oxygen is liberated by chemosynthesizing bacteria that produce energy. C. Oxygen is not used by plants during the day. D. Oxygen combines with sulfur to form an air pollutant when fossil fuels are burned. E. All of these statements are true.
The correct answer is D. Oxygen combines with sulfur to form sulfur dioxide, a pollutant, when fossil fuels are burned. As for the other answers, nitrogen is the most abundant gas in the atmosphere, chemosynthesizing bacteria release sulfur instead of oxygen, and oxygen is used by plants during the day to respire (however, oxygen liberated by photosynthesis often exceeds that used on sunny days).
What is the difference between production and productivity? A. Productivity is used for autotrophs, and production is used for heterotrophs. B. Production is used for autotrophs, and productivity is used for heterotrophs. C. Productivity is an amount of energy stored, and production is the amount stored over time. D. Production is an amount of energy stored, and productivity is a rate of production over time. E. There is no difference; these are synonymous terms for the same concept.
The correct answer is D. Productivity is usually more meaningful than production because it provides a timeframe in which energy accumulated.
Which of the following factors would not influence the Ecological Growth Efficiency? A. Ability for an animal to maintain its body temperature by physiological mechanisms B. Amount of energy lost in the urine C. Digestibility of the food resource D. Normal metabolism (more correctly called basal metabolic rate) E. Trophic level
The correct answer is E because carnivores generally have higher maintenance needs than herbivores but generally consume more digestible foods (i.e., there are no clear trends among trophic levels). All of the first four answers are factors that influence how much energy is removed from ingested energy, thereby influencing what is left for growth and reproduction.
Which of the following statements is true concerning various organisms in the nitrogen cycle? A. All microorganisms involved in the nitrogen cycle are various types of bacteria. B. Denitrifying organisms are bad because they convert useful forms of nitrogen into a form that cannot be used by most plants. C. Many nitrifying organisms are symbiotes in plant nodules. D. Decomposers are bad because they produce ammonium which is toxic at high levels. E. None of these statements are true.
The correct answer is E. All of the answers A through D are false. A) In addition to bacteria, some fungi and blue-green algae are involved in various steps of the nitrogen cycle. B) Denitrifying organisms remove excess nitrates from the environment, thereby reducing eutrophication in some ecosystems, and should not be considered "bad". C) Some nitrogen fixers, not nitrifying organisms, are symbiotes in plant roots. D) Decomposition is a valuable process that returns nutrients to the soil. Although ammonium can be toxic and is not readily accessible to plants, nitrifying organisms can convert it to nitrates.
Which of the following statements is true when comparing the various types of heterotrophs? A. Carnivores generally have longer intestines than herbivores. B. Herbivores feed on a mixture of plant and animal foods. C. Foods of omnivores are generally more difficult to catch than foods of carnivores. D. Foods of omnivores are generally easier to digest than foods of carnivores. E. None of the previous statements are true.
The correct answer is E. All of these statements are false. Animal foods are usually easier to digest than plant foods, so the intestine does not need to be as long in a carnivore. Herbivores eat only plants. Omnivores eat some plant foods which are much easier to "catch" than animals. Plants in the diet of omnivores make their diet more difficult to digest than those of carnivores.
Which of the following statements is not true about DDT? A. DDT was synthesized to control mosquito populations. B. DDT killed many non-target organisms. C. Concentrations of DDT in fish-eating birds reached levels 10 million times above the concentrations in water. D. DDT influenced the thickness of egg shells in birds, thereby resulting in reduced reproduction. E. Despite recommendations to ban DDT, it is still used as an insecticide today.
The correct answer is E. DDT was banned in the U.S. in 1972, but some residues still exist in the environment. Many populations of fish-eating birds are now recovering and appear to be only minimally affected by the residues.
As defined in this class, what is the correct term to define a group of trees that occur together in a forest if 10 species of trees are present? A. Population B. Community C. Ecosystem D. Biome E. None of the above.
The correct answer is E. Populations consist only of a single species. Communities consist of all living organisms in the ecosystem and not just trees. Ecosystems and Biomes consist of non-living components, in addition to living organisms. As defined in this class, there is not a correct term for just the trees alone. However, many ecologists would refer to this component as the "tree community". "Community" is more correct than "Population" because populations never consist of more than one species.
Which of the following is not part of the environment of a fish living in a pond? A. The other fish in the pond B. The invertebrates that the fish eats C. The logs under which the fish escapes from predators D. The water in the pond E. All of the above are part of the environment of the fish.
The correct answer is E. The environment includes all of the organism's surroundings, including living and non-living components.
