d. involves
e. occurs along different pathways
18. (Unit 2) Consider the following simple pond food chain where hawks feed on frogs, which feed on pond snails, which feed on algae.
Trophic Level Organism Total Available energy
Tertiary consumer hawk 1 kcal
Secondary consumer frog ?
Primary consumer pond snail ?
Primary producer algae ?
If 1 kcal of energy is available at the tertiary consumer level, how much energy will likely be available at the primary consumer level?
a. About 10,000 kcal because primary consumer level should always contain about 10,000 kcal energy compared to tertiary consumer.
b. About 10 kcal because there should be an equivalent amount of energy at each trophic level.
c. About 1000 kcal because each lower trophic level should contain 10 times more energy than the trophic level above it.
d. About 100 kcal because each lower trophic level should contain 10 times more energy than the trophic level above it.
