Ecosystem Levels of Organization

A scientist has been studying all the alligators in an east Texas swamp for 10 years. In the past five years, she has observed a large drop in their number. This scientist is studying the swamp's:

• a. alligator community

• b. alligator species

• c. alligator population

Answer explanation

All of the organisms belonging to the same species living in the same place are called a "population."

Here, the organisms are members of the alligator species. Together, these alligators live in a specific swamp in east Texas. So, the whole group of them is called the "population of alligators" in this swamp.

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-4

Scientists are concerned that the monarch butterfly ********** is at risk of dying out.

• a. species

• b. community

• c. organism

Answer explanation

The life and death of one, single organism is all part of the cycle of life. But when all members of a species start to die off, it is a reason for scientists to be concerned. When one monarch butterfly dies at the end of it's life cycle, it is natural and expected. If all monarch butterflies die, the entire species will be gone forever.

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-4

NGSS.MS-LS1-5

The Okefenokee Swamp is rich with living things, both plants and animals. It has a very diverse living **********.

• a. population

• b. community

• c. ecosystem

Answer explanation

"Community" is the correct answer because it means all the living things, both plants and animals, living in a specific place. We do not say a "diverse living ecosystem," because the ecosystem includes both the living AND the non-living parts of the place.

Tags

NGSS.MS-LS2-2

Worldwide there are 1.5 million different ********** of beetles.

• a. populations

• b. communities

• c. species

Answer explanation

There are many different kinds of beetles in the world (1.5 million). Each type of beetle is a particular species: These are the groups whose members share the same characteristics and can produce offspring together by mating. So, species is the correct answer.

If two organisms can mate and produce offspring together, they are known to be members of the same **********.

• a. community

• b. population

• c. species

• d. organism

Answer explanation

Only members of the same species can produce offspring together by mating, so the correct answer is species.

Tags

NGSS.MS-LS3-2

NGSS.MS-LS4-4

The Rio Grande river, the Chisos Mountains, and a diverse community of plants and animals together make up the desert ********** of Big Bend National Park.

• a. population

• b. community

• c. ecosystem

Answer explanation

The correct answer is "ecosystem," because the statement says both the non-living and living aspects of Big Bend National Park. The non-living parts are the river and the mountains. The living part is the "community of plants and animals."

Tags

NGSS.MS-LS2-2

NGSS.MS-LS2-3

Park rangers have counted 30-40 black bears in Big Bend National Park.

It is a small but thriving bear **********.

• community

• species

• population

• d. ecosystem

Answer explanation

While is is true that all the bears in this park are members of the same species, the correct answer is "population." A population is all the members of a species living together in a certain place.

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-4