Environmental Science: Carbon Cycle and Greenhouse Effect Worksheet

Question 1

Describe two ways carbon moves from the atmosphere into living things.

Accepted Answer

Carbon moves from the atmosphere into plants when plants take in carbon dioxide during photosynthesis. Carbon also moves into animals when animals eat plants or eat other animals that ate plants.

Question 2

A plant uses carbon dioxide, water, and sunlight to make sugar during photosynthesis. Explain how this process is part of the carbon cycle.

Accepted Answer

Photosynthesis is part of the carbon cycle because it removes carbon dioxide from the atmosphere and stores carbon in sugars and plant tissues.

Question 3

Explain what happens to carbon when a dead tree decomposes on a forest floor.

Accepted Answer

When a dead tree decomposes, decomposers break down its tissues. Some carbon is released as carbon dioxide into the atmosphere, and some carbon becomes part of the soil.

Question 4

Name two human activities that add carbon dioxide to the atmosphere and explain how each activity releases carbon.

Accepted Answer

Burning fossil fuels adds carbon dioxide because coal, oil, and natural gas contain carbon that is released when they burn. Cutting or burning forests adds carbon dioxide because stored carbon in trees is released and fewer trees remain to absorb carbon dioxide.

Question 5

A car burns gasoline on a trip. Identify the carbon reservoir the gasoline came from and the reservoir where much of the carbon goes after burning.

Accepted Answer

The gasoline came from fossil fuels, which are carbon reservoirs stored underground. After burning, much of the carbon becomes carbon dioxide and moves into the atmosphere.

Question 6

Explain the difference between carbon storage and carbon release in the carbon cycle.

Accepted Answer

Carbon storage happens when carbon stays in a reservoir such as forests, soil, oceans, or fossil fuels. Carbon release happens when carbon moves out of a reservoir, often as carbon dioxide, through processes such as respiration, decomposition, or combustion.

Question 7

The ocean absorbs a large amount of carbon dioxide from the air. Describe one way this helps the atmosphere and one possible problem it can cause in the ocean.

Accepted Answer

Ocean absorption can help the atmosphere by reducing the amount of carbon dioxide in the air. It can cause problems in the ocean because extra carbon dioxide can make seawater more acidic, which can harm shells, corals, and some marine organisms.

Question 8

In your own words, explain the greenhouse effect.

Accepted Answer

The greenhouse effect is the process in which gases in the atmosphere absorb and re-radiate heat from Earth. This keeps Earth warmer than it would be without those gases.

Question 9

List three greenhouse gases and identify the one most directly connected to burning fossil fuels.

Accepted Answer

Three greenhouse gases are carbon dioxide, methane, and water vapor. Carbon dioxide is the greenhouse gas most directly connected to burning fossil fuels.

Question 10

Explain why some greenhouse effect is necessary for life on Earth, but too much greenhouse effect can be harmful.

Accepted Answer

Some greenhouse effect is necessary because it keeps Earth warm enough for liquid water and living things. Too much greenhouse effect can be harmful because it can raise global temperatures and change weather patterns, sea levels, and ecosystems.

Question 11

A factory releases 500 units of carbon dioxide in one day. A nearby forest absorbs 120 units of carbon dioxide that day. Calculate the net amount of carbon dioxide added to the atmosphere.

Accepted Answer

The net amount added is 380 units of carbon dioxide. This is found by subtracting 120 units absorbed by the forest from 500 units released by the factory.

Question 12

A student says, "Carbon dioxide is always bad because it causes warming." Write a more accurate statement about carbon dioxide.

Accepted Answer

A more accurate statement is that carbon dioxide is a natural part of the carbon cycle and helps keep Earth warm, but too much carbon dioxide in the atmosphere can increase warming and affect climate systems.

Environmental Science: Carbon Cycle and Greenhouse Effect

Related Cheat Sheets

More Environmental Science Worksheets

More Grade 6-8 Worksheets