U4: L1 What is an Ecosystem?

An ecosystem is made of both biotic and abiotic things. Which describes the biotic part of the ecosystem?

• plants that grow in soil

• the animals that breathe oxygen

• all living things in the environment

• plants and animals that live in water

Tags

NGSS.MS-LS2-4

If you stand in the middle of an open field, you are standing among individual organisms, different species, populations, and communities. What makes up one of the populations in the field?

• all organisms of the same species

• the different communities in the ecosystem

• the communities that occupy the same niche

• all organisms that live in a certain part of the field

The rainforests in South America support many ecosystems. These ecosystems are healthy. How does the diversity in the rainforests help determine the health of ecosystems?

• When diversity is high, there are more resources available.

• Resources in the environment last longer when the diversity is low.

• Less diverse ecosystems have less competition among the residents.

• Areas with high diversity have increased competition among the residents.

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-2

NGSS.MS-LS2-4

NGSS.MS-LS2-5

Temperature, water, soil, and air are abiotic factors in an environment. They are not the same everywhere. What role do abiotic factors such as these play in an ecosystem?

• They control the changes of the seasons.

• They prevent competition among populations.

• They determine which plants and animals can live there.

• They help control the effect humans might have on the ecosystem.

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-4

When scientists talk about an ecosystem and the type and number of animals and plants that live in one, they are also concerned about limiting factors. What are limiting factors?

• the rate at which the plants and animals in an ecosystem reach maturity

• the ratio of animals that lay eggs and those that give birth to live young

• the things that are necessary to support a population of organisms in an

  area

• the difference between trees that lose their leaves in an ecosystem and those that don't

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-4