Question

Question 1
A)The primary source of energy in most ecosystems is/are(1 point)
Responses

autotrophs.
autotrophs.

heterotrophs.
heterotrophs.

the sun.
the sun.

glucose.
glucose.
Question 2
A)Which would be an autotroph in a grassland ecosystem?(1 point)
Responses

mallard duck
mallard duck

monarch butterfly
monarch butterfly

prairie cordgrass
prairie cordgrass

muskrat
muskrat
Question 3
A)Which of the following best explains why there are fewer secondary consumers than producers?(1 point)
Responses

More secondary consumers can absorb radiant energy from the sun.
More secondary consumers can absorb radiant energy from the sun.

Secondary consumers have less cell processes that need energy.
Secondary consumers have less cell processes that need energy.

Around 10% of the energy is transferred to support the next trophic level.
Around 10% of the energy is transferred to support the next trophic level.

Heat energy given off from producers kills off primary and secondary consumers.
Heat energy given off from producers kills off primary and secondary consumers.
Question 4
A)Which trophic level ingests the most biomass in order to receive the energy they need?(1 point)
Responses

secondary consumers
secondary consumers

producers
producers

tertiary consumers
tertiary consumers

primary consumers
primary consumers
Question 5
A)
Wolves were reintroduced to Yellowstone National Park in 1995. They began to hunt the abundant elk population, so elk numbers decreased. The elk carcasses provided food for other predators, like foxes, coyotes, and bears, so all of their populations increased. Elk used to overgraze on willow plants; now that willows are growing back, beaver numbers are increasing, because they prefer the slow-moving water that willows cause.

Which of these species is a keystone species?

(1 point)
Responses

willows
willows

bears
bears

wolves
wolves

elk
elk
page 12 of 12




Answer 1

Here are the correct responses based on your questions:

**Question 1**
A) The primary source of energy in most ecosystems is/are:
**Response:** **the sun.**

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**Question 2**
A) Which would be an autotroph in a grassland ecosystem?
**Response:** **prairie cordgrass.**

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**Question 3**
A) Which of the following best explains why there are fewer secondary consumers than producers?
**Response:** **Around 10% of the energy is transferred to support the next trophic level.**

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**Question 4**
A) Which trophic level ingests the most biomass in order to receive the energy they need?
**Response:** **producers.**

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**Question 5**
A) Which of these species is a keystone species?
**Response:** **wolves.**

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If you have any further questions or need additional clarification, feel free to ask!