Unit 4 quiz review

As global warming melts polar ice, fewer seals can be found in the Arctic. As a result, polar bears will most likely

• increase in number as competition with the seals for food increases.

• maintain a constant population by finding other sources of food.

• decrease in number as their food source disappears.

• migrate to tropical regions to follow the seals.

The pictures show organisms that obtain their primary source of energy from the Sun. Which of the following best classifies these organisms?

• producers

• decomposers

• first-level consumers

• second-level consumers

Why does Maria have to feed her hamster every day but only has to feed the roses in her yard once a month?

• Plants get most of their food from soil.

• Plants make their own food from sunlight.

• Plants take in food particles found in the air.

• Plants take in food particles in drops of water.

How are plants different from animals?

• They can make their own food using sunlight, air, and water.

• They have to get their energy from other plants and animals.

• They can live on land and in water.

• They do not need water to live.

The picture shows a model of an ecosystem. Which scenario would have the greatest effect on the organisms in this ecosystem?

• More birds begin to migrate into the area.

• Fish lay more eggs in the underwater plants.

• A tree in the ecosystem dies and begins to rot.

• Water in the pond of the ecosystem disappears.

Some organisms make their own food and some eat other organisms. Which of the following shows the proper flow of energy?

• grass → cow → sunlight

• sunlight → grass → cow

• cow → grass → sunlight

• grass → sunlight → cow

Why do carnivores depend on plants?

• Carnivores mainly eat plants, which give them nutrients.

• Carnivores mainly eat producers, which mainly eat plants.

• Carnivores mainly eat herbivores, which get their energy from plants.

• Carnivores mainly eat decomposers, which break down dead plants.

If humans build a large bridge over an area that has many small plants, what will most likely happen to the small plants?

• They will attract more nesting birds.

• They will grow better in the darkness.

• They will grow taller because they will get more food.

• They will die because they will not get as much sunlight.

Which of the following is a producer?

• bear

• trout

• tree

• human

Which of the following refers to a species that is no longer in existence after a change in their environment?

• endangered

• native

• extinct

• invasive