Matter and Energy in Ecosystems

Bob grows vegetables in the same soil year after year. The plants produce less and less vegetables each year. Which of these processes could help explain Bob's observation?

• the rate at which soil bacteria perform photosynthesis

• the rate at which soil bacteria perform denitrification

• the rate at which soil bacteria perform cellular respiration

• the rate at which soil bacteria perform nitrogen fixation

Tags

NGSS.MS-LS2-3

NGSS.MS-LS1-5

NGSS.MS-LS2-1

NGSS.MS-LS2-4

Organisms that take in energy from inorganic sources such as the sun or other chemicals to form energy rich compounds are called what?

• Heterotrophs

• Autotrophs

• Phototrophs

• Chemotrophs

Where do most of the producers get their energy source?

• sun

• consumers

• heterotrophs

• all the above

Tags

NGSS.MS-LS2-3

NGSS.MS-LS1-6

Which of the following is true of a model of feeding relationships in an ecosystem?

• There are several food chains, but not a food web

• There are several food chains and several food webs

• There is one food web, but no food chains

• There is one food web and several overlapping food chains

Tags

NGSS.MS-LS2-3

Angie constructs models of the carbon cycle, nitrogen cycle, and water cycle. What type of ecological modes are these?

• food web

• food chain

• biogeochemical cycles

• geological system

Tags

NGSS.MS-ESS2-4

What changes nitrates back to nitrogen gas in the atmosphere?

• photosynthesis

• cheosynthesis

• nitrification

• denitrification

Which statement describes all primary producers?

• all take in food and break it apart to release energy

• all are small, single-celled organisms, such as bacteria algae

• all take in energy to assemble energy-rich compounds

• all harness the energy of sunlight through the process of photosynthesis

Tags

NGSS.MS-LS1-6

Energy flows from primary producers to consumers, in one direction only

• True

• False

Tags

NGSS.MS-LS2-3

NGSS.MS-LS1-6

How much energy is available for secondary consumers?

• 100%

• 10%

• 1%

• 0.1%

Tags

NGSS.MS-LS2-3

In a pyramid of biomass in an ecosystem, the amount of biomass increases as you go up the pyramid.

• True

• False

Tags

NGSS.HS-LS2-3

NGSS.HS-LS2-4