Populations and Resources Review

When the number of births and deaths in a population is approximately the same, the population is said to be

• stable

• increasing

• multiplying

• decreasing

A population of tigers lives in Bangladesh. Over 50 years, the size of the tiger population increased. What best explains the increase in the size of the tiger population?

• A lot of tigers were born and none of them died.

• The tiger population is always increasing because no animal eats tigers.

• Fewer tigers were born than died.

• More tigers were born than died.

Tags

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

A large population of ducks lives in an area with a lake. In the last 40 years, the size of the duck population has stayed the same. What must be true about the duck population during the last 40 years?

• The number of ducks that were born was the same as the number of ducks that died.

• No ducks were born and no ducks died.

• Humans started protecting the duck population so they stopped dying.

• The ducks did not have any baby ducks during these years.

Tags

NGSS.MS-LS2-1

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?

• 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

A scientist who studies interactions of organisms with one another and their environment is a(n)

• archaeologist

• paleontologist

• ecologist

• geneticist

Within a population, organisms are always

• growing and shrinking

• running and walking

• being born and dying

• coming and going

Which of the following will lead to a population increase?

• Less births than deaths.

• More deaths than births

• equal deaths and births

• more births than deaths

The more organisms have of this, the more they can reproduce

• energy storage molecules

• air

• water

• organisms

Energy storage molecules come from the

• consumer population

• resource population

• food web

• reproduction