Populations and Resources

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.

• Fewer tigers were born than died.

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

• More tigers were born than died.

Tags

NGSS.MS-LS4-4

In this ecosystem, lizards eat fireflies, and fireflies eat gnats (a type of insect). Then the lizard population decreased suddenly. What will most likely happen to the size of the firefly population as a result?

• increase. The smaller lizard population will need fewer energy storage molecules so they will eat fewer fireflies. This will lead to fewer deaths than births in the firefly population.

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

• decrease. A decrease in any population causes a decrease in the sizes of all other populations in the ecosystem.

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-2

NGSS.MS-LS2-4

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

• stay the same. Opossums and foxes do not eat each other, so the number of births and deaths in the fox population will stay the same.

• decrease. Fewer energy storage molecules will be available to the fox population from the smaller rat population, so the fox population will reproduce less. This will lead to fewer births than deaths in the fox population.

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-LS2-4

In this ecosystem, lions eat wild pigs, and wild pigs eat frogs. The the frog population decreased suddenly. What will likely happen to the size of the wild pig population as a result?

• increase. The smaller frog population will need fewer energy storage molecules so there will be more energy storage molecules available to the wild pig population. This will lead to more births in the wild pig population.

• decrease. The smaller frog population will provide fewer energy storage molecules for the wild pig population, so the wild pig population will reproduce less. This will lead to fewer births than deaths in the wild pig population.

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

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-2

NGSS.MS-LS2-4

Over the span of 15 years, a populations of giraffes stayed the same. What statement is true about what is happening?

• No giraffes were born or died in the 15 year time span.

• The same amount of giraffes died that were born in the 15 year time span.

• More giraffes died than were born.

• More giraffes were born than died.

If the same amount of organisms are born and die in population, what will happen to its population?

• It will stay stable

• It will increase

• It will decrease

If there are more births than deaths in a population, what will happen to the population of organisms?

• increase

• decrease

• stay the same

Tags

NGSS.MS-LS2-4

If there are more deaths than births what will happen to a population of organisms?

• increase

• decrease

• stay the same

Tags

NGSS.MS-LS2-4

What do organisms need in order to reproduce?

• nothing

• air, sunlight, and food

• energy storage molecules

Tags

NGSS.MS-LS1-4