Question

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

heterotrophs.
heterotrophs.

glucose.
glucose.

autotrophs.
autotrophs.

the sun.
GPT-4o mini
The primary source of energy in most ecosystems is **the sun**.
Which would be an autotroph in a grassland ecosystem?(1 point)
Responses

muskrat
muskrat

mallard duck
mallard duck

monarch butterfly
monarch butterfly

prairie cordgrass
GPT-4o mini
In a grassland ecosystem, **prairie cordgrass** would be an autotroph.
Which of the following best explains why there are fewer secondary consumers than producers?(1 point)
Responses

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.

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

More secondary consumers can absorb radiant energy from the sun.
GPT-4o mini
The correct response is: **Around 10% of the energy is transferred to support the next trophic level.**
Which trophic level ingests the most biomass in order to receive the energy they need?(1 point)
Responses

primary consumers
primary consumers

producers
producers

secondary consumers
secondary consumers

tertiary consumers
GPT-4o mini
The correct response is: **producers.** Producers ingest the most biomass because they convert sunlight into energy through photosynthesis, forming the base of the food chain.
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

wolves
wolves

elk
elk

bears
GPT-4o mini
The correct response is: **wolves.** Wolves are considered a keystone species because their presence helps regulate the elk population, which in turn has cascading effects on the entire ecosystem, including vegetation and other animal populations.
When a consumer eats a producer, 10 percent of the producer’s energy is passed on to the consumer trophic level. What happens to the other 90 percent?(1 point)
Responses

It is used by the producer to pass on to the next trophic level.
It is used by the producer to pass on to the next trophic level.

It is consumed and used by the consumer.
It is consumed and used by the consumer.

It is added back to the soil by decomposers.
It is added back to the soil by decomposers.

It is used for cell processes or released as heat.
GPT-4o mini
The correct response is: **It is used for cell processes or released as heat.**