Aquatic Ecosystems

The base of the ocean’s food chains is formed by

• coral reefs

• whales

• plankton

• fish

The ocean floor, some parts of which get no sunlight, is the

• neritic zone

• intertidal zone

• oceanic zone

• benthic zone

Which of the following is NOT a key abiotic factor in marine ecosystems?

• water temperature

• amount of plankton

• water depth

• amount of sunlight

The area that contains the deep water of the open ocean and is where the sea floor drops sharply is the

• intertidal zone

• neritic zone

• oceanic zone

• benthic zone

The place where the ocean meets the land is the

• intertidal zone

• neritic zone

• oceanic zone

• benthic zone

The area that has warm, sunlit water, coral reefs, and is where the ocean floor begins to slope downward is the

• intertidal zone

• neritic zone

• oceanic zone

• benthic zone

Many plants can grow in the littoral zone of a lake because

• sunlight reaches its bottom.

• there are no algae.

• there is both salt water and fresh water.

• there are no animals.

Which of the following is a key abiotic factor in rivers?

• number of fish

• amount of salt

• speed of water

• how animals adapt

From where do plankton get food?

• photosynthesis

• insects

• small fish

• whales

What may happen as sediment and decaying organisms build up in a pond?

• The water may have more salt.

• The pond may become a lake.

• The pond may become a forest.

• More fish may live in the pond.