Question

1. all of the following are decomposers except

a. scavengers.
b. detritivores.
c. autotrophs.
d. saprophytes.

1. which trophic level of a food chain consists of secondary consumers?

a. trophic level 1
b. trophic level 2
c. trophic level 3
d. trophic level 4

1. about 10 percent of the energy at any given trophic level is

a. used for metabolic processes.
b. available for the next higher trophic level.
c. given off as heat to the environment.
d. used by producers such as plants to make food.

1. higher trophic levels tend to have

a. larger organisms.
b. more organisms.
c. more biomass.
d. two of the above

1. what do scavengers consume?

a. dead leaves
b. animal feces
c. dead animals
d. none of the above

Explanation:

Question 3

Decomposers break down dead organic matter. Scavengers (a) consume dead organisms, detritivores (b) feed on detritus, and saprophytes (d) are decomposers. Autotrophs (c) produce their own food (e.g., plants via photosynthesis) and are not decomposers.

Trophic levels: Level 1 - producers (autotrophs), Level 2 - primary consumers (herbivores), Level 3 - secondary consumers (carnivores that eat herbivores), Level 4 - tertiary consumers. Secondary consumers are at trophic level 3.

The 10% energy transfer rule: About 10% of energy at one trophic level is available (transferred) to the next higher trophic level. Energy is used for metabolism (a) and lost as heat (c), so the remaining ~10% is available for the next level (b). Option d is incorrect as producers use energy to make food (but this is about energy transfer between levels, not producer energy use).

Answer:

c. autotrophs.

Question 4