Populations & Resources Review

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?

• Increase

• Decrease

• Stay the same

In a rainforest, anteaters eat ants, and ant eat aphids (a type of very small insect.)  The sizes of the populations have been stable for the last 10 years, but recently the size of the aphid population decreased.

What will likely happen to the anteater population

• Increase

• Decrease

• Stay the Same

The data showed that recently the alligator population has decreased. 

How could the decrease in the alligator population affect the other populations?

Select all of the changes that would occur in the populations.

• The gar population would increase

• The gar population would decrease

• The duck population would increase

• The duck population would decrease

• The crab population would decrease

Organisms are classified as producers or consumers according to the way they ________________.

• Obtain energy

• release waste

• produce offspring

• move from place to place

What do mammals like lions and cheetahs need energy for?

• running

• breathing

• digesting food

• all of the above

Scientists have been studying the size of three populations along the coast of Antarctica.  In this ecosystem, penguins eat sardines (a type of small fish), and sardines eat zooplankton (very small animals that live in water).  The data showed that all three populations were stable.  Then the penguin population decreased suddenly.  

What will likely happen to the size of the sardine population as a result?

• Increase

• Decrease

• Stay the same

Scientists have been studying the size of three populations in a grassland.  In this ecosystem, lizards eat fireflies, and fireflies eat gnats (a type of insect).  The data showed that all three populations were stable.  Then the lizard population decreased suddenly.

What will most likely happen to the size of the firefly population as a result?

• Increase

• Decrease

• Stay the Same

Scientists have been studying the size of three populations in a swampland.  In this ecosystem, heron (a type of bird) eat frogs, and frogs eat dragonflies.  The data showed that all three populations were stable.  Then the dragonfly population increased suddenly.

What will likely happen to the frog population as a result?

• Increase - The larger dragonfly population will provide more energy storage molecules for the frog population, so they will reproduce more.  This will lead to more births than deaths in the frog population.

• Increase - An increase in any population within an ecosystem causes an increase in the sizes of all other populations in the ecosystem.

Which statement would be true if the owl population disappeared?

• The mouse population would increase

• The carrot population would increase

• The fox population would decrease

• The rabbit population would decrease

An organism, such as a cow or a human, that eats a plant obtains the energy stored in the plant. An animal that eats a producer is a primary consumer. An animal that eats a primary consumer is a secondary consumer Some types of organisms, such a fungi and certain bacteria, obtain energy by breaking down the remains of dead organisms.

Which of these organisms is a primary consumer?

• Wolf

• Oak Tree

• Horse

• Mushroom