Ocean Food Webs

Question 1

If a small fish that eats zooplankton disappears from an ocean food web, which of the following is most likely to happen?

Accepted Answer

Zooplankton would become more abundant, and the larger predators that ate the small fish would have less food.

Answer

All the other animals would immediately die, leaving the ocean empty.

Answer

Nothing would change because other fish would quickly fill the missing role.

Answer

Only the phytoplankton would disappear from the ocean.

Question 2

Which choice shows two correct ways that energy can move through an ocean food web, starting with phytoplankton?

Accepted Answer

Phytoplankton → Zooplankton → Small fish → Seal, and Phytoplankton → Zooplankton → Small fish → Shark

Answer

Phytoplankton → Small fish → Zooplankton → Seal, and Phytoplankton → Zooplankton → Shark → Small fish

Answer

Zooplankton → Phytoplankton → Small fish → Seal, and Phytoplankton → Small fish → Seal → Shark

Answer

Phytoplankton → Zooplankton → Shark → Small fish, and Phytoplankton → Small fish → Seal → Zooplankton

Question 3

In a coastal ocean food web, kelp is eaten by sea urchins, sea urchins are eaten by sea otters, and sea otters are eaten by killer whales. If sea otters disappear from the web, which of the following describes what is most likely to happen?

Accepted Answer

Sea urchin numbers would rise, the kelp would be eaten away, and fish that live among the kelp would have less food and become fewer.

Answer

Sea urchin numbers would fall, the kelp would grow more, and there would be many more fish living among the kelp.

Answer

Nothing would change because other animals would start eating the sea urchins in the same way the otters did.

Answer

Killer whales would have more food and their numbers would double, keeping the web balanced.

Try three questions

If a small fish that eats zooplankton disappears from an ocean food web, which of the following is most likely to happen?

Which choice shows two correct ways that energy can move through an ocean food web, starting with phytoplankton?

In a coastal ocean food web, kelp is eaten by sea urchins, sea urchins are eaten by sea otters, and sea otters are eaten by killer whales. If sea otters disappear from the web, which of the following describes what is most likely to happen?

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