MC	Biology	Standard: 01
Objective: 01. Summarize how energy flows through an ecosystem.
ILO:

Which of the following is a complete and correctly organized food chain?

a. alfalfa ˆ grasshopper ˆ cow ˆ bot fly ˆ barn swallow

b. barley ˆ aphid ˆ ladybird beetle

c. grass ˆ grasshopper ˆ warbler ˆ praying mantis

d. algae ˆ fish ˆ coyote ˆ snake

e. aspen ˆ bacteria ˆ grasshopper ˆ warbler

Correct Answer: b

MC	Biology	Standard: 01
Objective: 01. Summarize how energy flows through an ecosystem.
ILO:

Which of these describes a pathway of energy through the living system?

a. Light energy ˆ chemical energy ˆ heat.

b. Light energy ˆ heat ˆ chemical energy.

c. Heat ˆ light energy ˆ chemical energy.

d. Chemical energy ˆ heat ˆ light energy.

Correct Answer: a

MC	Biology	Standard: 01
Objective: 01. Summarize how energy flows through an ecosystem.
ILO:

Which of the following statements best describes the work done by decomposers?

a. They provide calcium for plants by taking it from the soil or water.

b. They release carbon from dead bodies in the form of carbon dioxide.

c. They create new sources of oxygen and release free nitrogen.

d. They prevent the escape of energy to outer space.

Correct Answer: b

MC	Biology	Standard: 01
Objective: 01. Summarize how energy flows through an ecosystem.
ILO:

Which organisms are most immediately necessary for the survival of primary consumers?

a. Producers

b. Decomposers

c. Secondary consumers

d. Tertiary consumers

Correct Answer: a

MC	Biology	Standard: 01
Objective: 01. Summarize how energy flows through an ecosystem.
ILO:

Which of the following statements is true regarding ecosystems?

a. Ecosystems support a larger number of heterotrophs than autotrophs.

b. The presence or absence of carnivores has a greater effect on ecosystems than the presence or absence of producers.

c. There are more organisms in the third trophic level than in the second trophic level.

d. The number of organisms decreases at each level of a food chain in an ecosystem.

Correct Answer: d

MC	Biology	Standard: 01
Objective: 01. Summarize how energy flows through an ecosystem.
ILO:

What happens to the amount of available energy at each level of a food chain?

a. The amount of available energy increases at each level.

b. The amount of available energy decreases at each level.

c. The amount of available energy remains the same at each level.

d. The amount of available energy changes depending on the number of organisms in the level.

Correct Answer: b

MC	Biology	Standard: 01
Objective: 01. Summarize how energy flows through an ecosystem.
ILO:

What would you predict might happen in an ecosystem if the number of organisms in the third trophic level exceeded the number of organisms in the second trophic level?

a. Nothing would change.

b. The number of organisms in the second trophic level would increase.

c. The number of organisms in the third trophic level would continue to increase.

d. The number of organisms in the third trophic level would decrease.

Correct Answer: d

MC	Biology	Standard: 01
Objective: 01. Summarize how energy flows through an ecosystem.
ILO:

In a food chain, which trophic level would have the greatest amount of available energy?

a. First

b. Second

c. Third

d. Fourth

Correct Answer: a

MC	Biology	Standard: 01
Objective: 01. Summarize how energy flows through an ecosystem.
ILO:

In a food chain, which trophic level would contain the greatest number of organisms?

a. First

b. Second

c. Third

d. Fourth

Correct Answer: a

MC	Biology	Standard: 01
Objective: 01. Summarize how energy flows through an ecosystem.
ILO:

Which statement most accurately describes what happens to energy as it moves through an ecosystem?

a. It is returned to the environment in the form of heat.

b. It increases as it moves through each level of the food chain.

c. It is used up by the time it reaches the third trophic level.

d. Each organism uses 50% of the energy and stores 50% to be used by other organisms.

Correct Answer: a

MC	Biology	Standard: 01
Objective: 01. Summarize how energy flows through an ecosystem.
ILO:

In order to construct your own food web, what information do you need to know?

a. how many organisms of each species

b. where the organisms live

c. how long they have lived

d. what the organisms consume

Correct Answer: d

MC	Biology	Standard: 01
Objective: 01. Summarize how energy flows through an ecosystem.
ILO:

In areas of southern California where humans have heavily hunted sea lions, killer whales (which normally hunt sea lions) are preying on sea otters. Which statement best describes why killer whales are hunting sea otters?

a. Sea otters are now easier to locate, hunt and kill than sea lions.

b. Sea otters provide more nourishment than killer whales.

c. Sea lions have evolved adaptations that protect them from killer whales.

d. Killer whales prefer sea otters over sea lions.

Correct Answer: a

MC	Biology	Standard: 01
Objective: 01. Summarize how energy flows through an ecosystem.
ILO:

Use the following key to answer the questions that follow:

KEY:

a. First-order consumers

b. Second-order consumers

c. Producers

d. Decomposers

_____ 1. Able to capture energy in the process of photosynthesis.

_____ 2. Organisms in a food web most likely to show an increase in number first.

_____ 3. Collects and converts carbohydrates to protein

_____ 4. Mice that eat grass

_____ 5. Hawks that eat mice who eat grass

_____ 6. Mosquitoes that bite cows

_____ 7. Organisms that digest dead plant and animal tissues

_____ 8. Purple bacteria which convert CO2 to cell substances, but utilize H2S instead of H2O

_____ 9. Carbon is made available to most organisms by the activities of these

_____ 10. Has the ability to change light energy to chemical energy

_____ 11. Most of these organisms are microscopic

Correct Answers:

1. c

2. c

3. a

4. a

5. b

6. b

7. d

8. c

9. c

10. c

11. d

MC	Biology	Standard: 01
Objective: 01. Summarize how energy flows through an ecosystem.
ILO:

Use the following key to classify the statements below:

KEY:

a. Producers

b. Consumers

c. Both consumers and producers

d. Neither consumers nor producers

_____ 1. Convert light energy into chemical energy

_____ 2. Supply food for consumers

_____ 3. Use the energy of sunlight to manufacture food

_____ 4. Have the ability to create energy

_____ 5. Are unable to make their own food

_____ 6. Have the ability to store energy in chemical bonds

_____ 7. Depend on organic molecules for food

Correct Answers:

1. a

2. c

3. a

4. d

5. b

6. c

7. b

MC	Biology	Standard: 01
Objective: 01. Summarize how energy flows through an ecosystem.
ILO:

Arctic terns migrate from their breeding grounds in the Arctic during the summer to South America for the winter. Which statement best describes the function of the migration?

a. Birds are warm blooded, and temperatures are too cold in the Arctic for the birds to survive.

b. Their energy needs can be met at either location; the birds are choosing a new habitat based on changes in weather.

c. The birds require a different habitat for breeding and nesting.

d. Energy requirements for the term cannot be met in the Arctic during the winter.

Correct Answer: d

MC	Biology	Standard: 01
Objective: 01. Summarize how energy flows through an ecosystem.
ILO:

Marmots hibernate when temperatures fall below 15.5 degrees Celsius. During hibernation, marmots breathe very slowly, circulation of blood is reduced, body temperature drops, and they are able to survive on their own reserves of fat. Which statement best describes the main adaptive advantage of hibernation?

a. Temperatures in the forest drop too low for the marmot to survive the winter.

b. Hibernation allows the marmotsÕ bodies to recover from the stress of summer.

c. Many predators are active during the winter; hibernation allows the marmot to avoid being eaten.

d. Food sources are scarce in the winter; the marmot would expend debilitating amounts of energy trying to obtain food.

Correct Answer: d

MC	Biology	Standard: 01
Objective: 01. Summarize how energy flows through an ecosystem.
ILO:

When wolves are introduced into a new area, they often will drive resident coyote populations typically decline. Which of the statements below is the best explanation for the wolvesÕ behavior?

a. Coyotes compete with wolves for the same prey base. Because wolves are bigger and stronger, they out compete for coyotes for major food sources.

b. Coyotes and wolves both use dens to protect their young. But wolves quickly occupy all available den sites.

c. If the coyotes do not leave, wolves will actually chase the adults away.

d. Wolves and coyotes are both in the genus Canidae, but because wolves are characteristically social animals, they are able to dominate the coyote population.

Correct Answer: a

I	Biology	Standard: 01
Objective: 01. Summarize how energy flows through an ecosystem.
ILO:

Study the following diagram and answer the questions that follow:

Questions:

1. In this food web, the hawk would be a third-level consumer if he ate

a. Seed-eating birds

b. Pocket gophers

c. Rabbits

d. Snakes

2. In terms of numbers of individuals, you would expect to find more

a. Snakes than gophers

b. Frogs than insects

c. Insects than insect-eating birds

d. Coyotes than rabbits

3. The best examples of primary consumers would be

a. Insects and seed-eating birds

b. Rabbits and owls