Question

1. there are less tertiary (3rd level) consumers in the biosphere because

a. more energy is available to support organisms at that level.
b. population size is the largest at that level.
c. less energy is available to support organisms at that level.
d. they are often eaten by predators.

1. which of the following shows the correct amount of energy for each trophic level in the pyramid above when moving from producers to tertiary (3rd level) consumers?

a. 0.1% > 1.0% > 10% > 100%
b. 1% > 100% > 10% > 0.1%
c. 100% > 10% > 1.0% > 0.1%
d. 100% >10% > 0.1% > 1%

1. as a group, which species holds more energy? hint: think about where they are on the energy pyramid.

a. rabbits
b. snakes
c. hawks
d. frogs

1. a coyote is

a. a carnivore and an autotroph.
b. a heterotroph, a consumer, and a carnivore.
c. an herbivore, a consumer, and an autotroph.
d. an autotroph and a heterotroph

1. which species exist at every trophic level but are not usually shown on the energy pyramid?

a. heterotrophs
b. autotrophs
c. consumers
d. decomposers

Explanation:

• Question 28: According to the energy pyramid concept in ecology, energy decreases as we move up trophic levels. Tertiary consumers are at a higher trophic level, so less energy is available to support them. Option c is correct as it aligns with this principle. Options a and b are incorrect because more energy is available at lower trophic levels (where producers are) and population size is larger at lower levels. Option d is not the main reason for fewer tertiary consumers compared to the energy - availability factor.
• Question 29: In an energy pyramid, producers (first trophic level) have the most energy (assigned as 100% for simplicity in such models). As we move to primary consumers (second level), about 10% of the producer's energy is available. For secondary consumers (third level), it's about 1% (10% of the 10% from primary consumers), and for tertiary consumers (fourth level), it's about 0.1% (10% of the 1% from secondary consumers). So the order is \(100\%>10\% > 1.0\%>0.1\%\), which is option c.
• Question 30: Rabbits are primary consumers (herbivores). Snakes can be secondary or tertiary consumers, hawks are usually tertiary consumers, and frogs can be secondary consumers. Since energy decreases at higher trophic levels, the group at the lower trophic level (rabbits - primary consumers) has more energy. So option a is correct.
• Question 31: A coyote is a carnivore (eats other animals). It is a heterotroph (cannot produce its own food) and a consumer (relies on other organisms for food). Autotrophs produce their own food (like plants), and herbivores eat plants. So option b is correct as it correctly classifies the coyote as a heterotroph, consumer, and carnivore.
• Question 32: Decomposers (like fungi and bacteria) act at every trophic level by breaking down dead organisms (from producers to top - level consumers). But they are not usually shown on the energy pyramid (which mainly focuses on the flow of energy through feeding relationships in a linear trophic structure). Heterotrophs include consumers and decomposers but the more specific answer is decomposers. Autotrophs are mainly at the producer level, and consumers are in specific trophic levels. So option d is correct.

Answer:

• 28. C. less energy is available to support organisms at that level.
• 29. C. \(100\%>10\% > 1.0\%>0.1\%\)
• 30. A. rabbits
• 31. B. a heterotroph, a consumer, and a carnivore.
• 32. D. decomposers