AP Environmental Science : Trophic Levels

Study concepts, example questions & explanations for AP Environmental Science

varsity tutors app store varsity tutors android store

Example Questions

Example Question #3 : Energy And Biochemical Cycles

Which of the following is likely to be in the lowest trophic level?

Possible Answers:

Cardinal

Caterpillar

Maple tree

Fox

King snake

Correct answer:

Maple tree

Explanation:

Trophic levels are related to the transfer of energy in the food chain. Predators and members of the "top of the food chain" occupy higher trophic levels, while energy producers occupy the lower levels. The correct order from lowest to highest should be the maple tree, caterpillar, cardinal, king snake, and then the fox.

Example Question #2 : Trophic Levels

Which of the following terms refers to the feeding levels of categories of organisms in  a commnunity?

Possible Answers:

Producers

Primary consumers

Trophic level

Secondary consumers

Teritiary consumer

Correct answer:

Trophic level

Explanation:

Trophic level (feeding level) describes the categories of organisms in a community, and the position of an organism in a food chain, defined by the organism's source of energy; includes producers (a photosythetic organism i.e. plants), primary consumers (an organism that feeds on producers; an herbivore), secondary consumers (an organism that feeds on a primary consumer;a carnivore), a tertiary consumer that feeds on other carnivores.

Example Question #4 : Energy Dynamics

All of the terms refer to organisms that are not any level of consumer except...?

Possible Answers:

Decomposer

Omnivore

Scavenger 

Detritivore 

Correct answer:

Omnivore

Explanation:

Scavenger, Detritivores and Decomposers are not any level of consumer since neither consumes any kind of living organism. Scavengers consume already dead organisms. Detritivores consume litter and dung. Decomposers break down biomass into nutrients. Only omnivores consume living organisms since they feed on both primary and secondary consumers. 

Example Question #2 : Trophic Levels

What percentage of overall energy is present in the biomass from a lower trophic level to the next highest one? 

Possible Answers:

20%

10%

50%

15%

Correct answer:

10%

Explanation:

Because of the law of conservation of energy, it cannot be 100% since some of the energy in each trophic level must be consumed by the organisms themselves. The energy is lost as heat through metabolic activities and other day to day expenditures. This number is supported due to the high number of producers and only a slight number of primary consumers in comparison. 

Learning Tools by Varsity Tutors