Cycles Worksheet b386h

Integrated Science

Name ____________________________

Cycles worksheet Please answer the following using the words in the text box. Carbon Cycle Coal

Oil

Photosynthesis

Natural Gas Respiration

ocean

burning of fossil fuels sugar

Greenhouse

volcanoes decayed

1. Plants use CO2 in the process of ___________________ to make ___________ and oxygen. 2. Animals use oxygen in the process of _______________ and make more CO2. 3. The ____________ is the main regulator of CO2 in the atmosphere because CO2 dissolves easily in it. 4. In the past, huge deposits of carbon were stored as dead plants and animals __________. 5. Today these deposits are burned as fossil fuels, which include _____________, _______________, and ______________. 6. More CO2 is released in the atmosphere today than in the past because of _________ ___________________ . 7. Another natural source for CO2 is __________________. 8. Too much CO2 in the atmosphere may be responsible for the _______________ effect. 9. Write the equation for photosynthesis.

10. Draw a simple diagram of the Carbon Cycle using the words in the text box above.

Oxygen Cycle Photosynthesis

Ozone

Waste

Crust

Oceans

Respiration

1. Plants release 430-470 billion tons of oxygen during process of _________________. 2. Atmospheric oxygen in the form of ___________ provides protection from harmful ultraviolet rays. 3. Oxygen is found everywhere on Earth, from Earth’s _____________ (rocks) to the ______________ where it is dissolved. 4. Oxygen is vital for ________________ by animals, a process which produces CO2.and water. 5. Oxygen is also necessary for the decomposition of ______________ into other elements necessary for life. 6. Write the equation for respiration.

7.

Draw a diagram of the Oxygen Cycle using the words in the text box.

Sulfur Cycle Water

Minerals

Volcanoes

minerals

Industry

Rain

pollution

matches

H2S

insecticide

Ground or rocks sulfuric acid

1. Sulfur in a pure elemental state is most often found near active ________________. 2. Sulfur is found in all of Earth’s environments, including the air, the hydrosphere (________), the biosphere (living part), and the lithosphere (____________or ________).

3. Many sulfates, a solid form of sulfur, come from chemical weathering of _____________ that contain sulfur. 4. Another major source of sulfur is from ______________ caused by man-made activities. These are mixed with water in the air falling in __________ into water basins. 5. The gas _______ smells like rotten eggs. 6. One of the most important sulfur compounds is ______________ ________, which is used to make fertilizers, automobile batteries, iron and steel, and plastics. 7. Other uses for sulfur include ______________ (kills insects) and __________ (used to start fires). 8. Make a diagram of where sulfur in found. Hint: See question #2 above.

Phosphorus Cycle Pollution

basins

rocks and minerals

waste

DNA

overgrowth

plants

1. Phosphorus in NOT found in the free state in Nature, but is contained mostly in _______ and ______________. 2. It is an essential nutrient for life, as it makes up important chemicals such as _______. 3. In the Phosphorus Cycle, phosphorus moves between the soil and ___________, which are eaten by animals. The animals use phosphorus, and then their ___________ products help return the Sulfur for the next generation of phosphorus in the soil. 4. Some of the phosphorus in soils can be washed away into water ___________. 5. Another source of phosphorus in water comes from man-made _____________. 6. Too much phosphorus in water leads to plant ________________, strangling all other life forms in the water. 7. Why is the use of too much phosphorus-rich fertilizers bad for the environment?

Nitrogen Cycle Atmosphere Nitrate

78% nitrogen-fixing

ammonia plants

proteins animals

denitrificating waste

plants

1. Our atmosphere is ______ nitrogen gas. 2. Animals and plants cannot directly use all the nitrogen found in our ________________. 3. Only special bacteria can directly use nitrogen in our atmosphere and “fix” it so other organisms can benefit. These bacteria are called ____________-_________ bacteria. 4. Higher organisms use nitrogen to make their _____________. 5. Animal waste decay by the action of bacteria which create _____________and __________ products rich in nitrogen, and useful for plants to use again. 6. ______________ bacteria in the soil can break down the ammonia into the gaseous form of nitrogen, which is not available for use by plants or animals. 7. In another part of the cycle, animals eat ____________ containing nitrogen, which is again returned to the soil by animal _____________ or decaying ____________ and ___________. 8. Draw a diagram of the Nitrogen cycle using the words in the text box.