Population and Resources Juncture Assessment

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 . . .

• decrease. The larger crab population will leave fewer energy storage molecules available in the ecosystem for the shark population, so there would be fewer births in the shark population.

• increase. An increase in the size of any population leads to an increase in the sizes of all other populations in an ecosystem.

• increase. More energy storage molecules will be available to the shark population from the larger whale population, so the shark population will reproduce more. This will lead to more births than deaths in the shark population.

• stay the same. Sharks do not eat crabs, so the number of births and deaths in the shark population will stay the same.

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-2

NGSS.MS-LS2-4

Scientists have been studying the size of three populations in a swampland. In this ecosystem, herons (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? The size of the frog population will . . .

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

• 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.

• stay the same. The size of its consumer population did not change, so the number of deaths in the frog population did not change. There will be the same number of births and deaths in the frog population.

• decrease. The larger dragonfly population will take more energy storage molecules from the ecosystem, leaving fewer available for the frog population. This will lead to fewer births in the frog population.

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-2

NGSS.MS-LS2-4

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 . .

• stay the same. Eagles and bears do not eat each other, so the number of births and deaths in the bear population will stay the same.

• increase. The smaller eagle population will leave more energy storage molecules for all other populations in the ecosystem, so all populations will reproduce more. This will lead to more births in the bear population.

• increase. More energy storage molecules will be available to the bear population from the larger trout population, so the bear population will reproduce more. This will lead to more births than deaths in the bear population.

• decrease. A decrease in the size of one population leads to a decrease in the sizes of all other populations in an ecosystem.

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-2

NGSS.MS-LS2-4

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 . . .

• stay the same. The size of their resource population did not change, so the amount of energy storage molecules available for the deer did not change. There will be the same number of births and deaths in the deer population.

• increase. An increase in the size of one population leads to an increase in the sizes of all other populations in the ecosystem.

• decrease. The larger puma population will leave fewer energy storage molecules available in the ecosystem for the deer. The deer population will reproduce less, leading to fewer births in the deer population.

• decrease. The larger puma population will need more energy storage molecules, so they will eat more deer. This will lead to more deaths than births in the deer population.

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-2

NGSS.MS-LS2-4

In the Arctic region, polar bears eat seals, and seals eat cod (a type of fish). In the last 7 years, the sizes of all the populations stayed stable, but recently the size of the polar bear population decreased. What will likely happen to the cod population? The size of the cod population will . . .

• decrease. A decrease in the size of one population leads to a decrease in the sizes of all other populations in an ecosystem.

• decrease. The smaller polar bear population will lead to more seals. The larger seal population will need more energy storage molecules to reproduce, so they will eat more cod. This will lead to more deaths than births in the cod population.

• stay the same. Polar bears do not eat cod, so the number of births and deaths in the cod population will stay the same.

• increase. The smaller polar bear population will leave more energy storage molecules available in the ecosystem for the cod population, so there will be more births in the cod population.

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-2

NGSS.MS-LS2-3

NGSS.MS-LS2-4

Scientists have been studying four populations in one area of the Atlantic Ocean. In this area, both tuna and dolphins eat squid, and squid eat herring (a type of fish). The data shows that recently the tuna population increased. How will the increase in the tuna population affect the other populations?

• Increase Herring

• Decreased Herring

• Same Amount of Herring

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-2

NGSS.MS-LS2-3

NGSS.MS-LS2-4

Scientists have been studying four populations in a swamp area. In this area, alligators eat gar (a type of large fish), and both gar and diving ducks eat crabs. The data showed that recently the alligator population has decreased. How could the decrease in the alligator population affect the other populations? The data showed that recently the alligator population has decreased. How could the decrease in the alligator population affect the other populations?

• More Gar

• Fewer Gar

• Gar stay the same

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-4

Scientists have been studying four populations in a swamp area. In this area, alligators eat gar (a type of large fish), and both gar and diving ducks eat crabs. The data showed that recently the alligator population has decreased. How could the decrease in the alligator population affect the other populations? The data showed that recently the alligator population has decreased. How could the decrease in the alligator population affect the other populations?

• More Crabs

• Fewer Crabs

• Same Amount of Crabs

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-2

NGSS.MS-LS2-4

Scientists have been studying four populations in one area of the Atlantic Ocean. In this area, both tuna and dolphins eat squid, and squid eat herring (a type of fish). The data shows that recently the tuna population increased. How will the increase in the tuna population affect the other populations?

• Increase Squid

• Decrease Squid

• Same Amount of Squid

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-2

NGSS.MS-LS2-4

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.

• More bluefish were born than died.

• Fewer bluefish were born than died.

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

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-4