Chapter 20 Earth's Ecosystems Review

Which of the following is a biotic factor in a biome?

• kinds of birds

• amount of rainfall

• types of rocks

• bodies of water

The speed of water is an important abiotic factor in a freshwater ecosystem because

• a tributary has different plants than a river.

• faster water has a higher salt content

• animals must adapt so they are not washed away.

• animals cannot live in fast-moving water.

One important abiotic factor in marine ecosystems is the

• amount of plankton

• water depth

• kinds of algae

• size of animals

Most of the nutrients in a tropical rain forest are found in plants, so

• the rain forest soil is very rich.

• there are few plants in the rain forest.

• there are few animals in the rain forest

• the rain forest soil is poor in nutrients.

From where do plankton get food?

• small fish

• insects

• photosynthesis

• whales

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

• The pond may become a lake.

• More fish may live in the pond.

• The water may have more salt.

• The pond may become a forest.

How can the littoral zone of a lake or pond be described?

• an area with no sunlight.

• an area with no animal life

• an area with no plant life

• an area closest to the edge of a lake or pond

has permafrost, in the Arctic or Antarctic.

• savanna

• desert

• polar tundra

• alpine tundra

has many tree that do not change much seasonally.

• temperate deciduous forest

• coniferous forest

• temperate grassland

• savanna

has organisms with special adaptations to a hot, dry climate.

• coniferous forest

• temperate grassland

• savanna

• desert