Populations Quiz

When a population is stable:

• the are fewer births than deaths

• the number of births and deaths are equal

• the number of births is greater than the number of deaths

• organisms are not dying or being born at all

If owls are eating mice and getting energy storage molecules from the mice, which is the resource population?

• owls

• mice

In Australia, both opossums and foxes eat rats. The sizes of the populations have been stable for the last 12 years, but recently the size of the opossum population increased. What will likely happen to the fox population?

The size of the fox population will . . .

• increase because there will be more rats to make energy.

• decrease because the opossum population is taking more energy storage molecules from the rats.

• stay the same because there are still energy storage molecules available.

• decrease because the opossum population is using the fox population for energy storage molecules.

A population of bluefish lives in the Gulf of Mexico. Over the last 50 years, the size of the bluefish population has decreased. What best explains the decrease in the size of the bluefish population?

• A lot of bluefish died and no new bluefish were born.

• Fewer bluefish were born than died.

• More bluefish were born than died.

• The bluefish population is always decreasing because bluefish are always being eaten.

In the Arctic Ocean, sharks eat whales, and whales eat crabs. In the last 10 years, the sizes of the populations have been stable, but recently the size of the crab population increased. What will likely happen to the shark population?

The size of the shark population will . . .

• increase

• decrease

• stay the same

In North America, both bears and eagles eat trout. The sizes of the populations have been stable for the last 9 years, but recently the size of the eagle population decreased. What will likely happen to the bear population?

The size of the bear population will . . .

• increase

• decrease

• stay the same

Scientists have been studying the size of three populations in Peru. In this ecosystem, pumas (large wild cats) eat deer, and deer eat grass. The data showed that all three populations were stable. Then the puma population increased suddenly. What will most likely happen to the size of the deer population as a result?

The size of the deer population will . . .

• increase

• decrease

• stay the same

Where does the energy that travels through an ecosystem originally come from?

• Earth's Core
• Water
• Plants
• The Sun

Recently, a family of bobcats moved into an area with a large rabbit population. What changes may occur in the ecosystem?

• The rabbit population may increase
• The rabbit population may decrease
• The rabbit population may increase first, then decrease
• The rabbit population will remain the same

Which of the following organisms in competition with the weasel for their food source?

• grass

• rabbit

• fox

• snake