5-2 The Cycling of Matter

1. 5-2 The Cycling of Matter Page 124

2. A. The Carbon Cycle • 1. The carbon cycle is the process in which carbon is recycled between the water, land, air and organisms.

3. A. The Carbon Cycle • 2. Plants convert the carbon in carbon dioxide to sugars through photosynthesis.

4. A. The Carbon Cycle • 3. When consumers eat producers, they obtain the carbon through the carbohydrates (sugars).

5. A. The Carbon Cycle • 4. Consumers break down carbohydrates (sugars) through cellular respiration and release it as carbon dioxide gas.

6. Think about it! • How do humans affect the carbon cycle? • Is this impact positive or negative on the environment?

7. A. The Carbon Cycle • 5. How do humans affect the carbon cycle? • Burning of fossil fuels releases CO2 • Increased CO2 (greenhouse gas) contributes to climate change, warming the atmosphere • Oceans absorb dissolved carbon which lower the pH, making oceans more acidic Video

8. B. The Nitrogen Cycle • 1. Nitrogen is needed to build new proteins.

9. B. The Nitrogen Cycle • 2. Nitrogen needs to be converted to a usable form by nitrogen-fixing bacteria.

10. B. The Nitrogen Cycle • 3. The Nitrogen cycle recycles Nitrogen through the atmosphere, soil, and organisms. Animation

11. B. The Nitrogen Cycle • 4. Decomposers are an essential part of the nitrogen cycle because they release nitrogen from wastes (urine, dung, decaying leaves, etc.)

12. C. The Phosphorous Cycle • 1. Phosphorous is an important element that makes up parts of cells such as bones and teeth.

13. C. The Phosphorous Cycle • 2. Plants get Phosphorous from soil/water, animals eat plants or other animals to get phosphorous.

14. C. The Phosphorous Cycle • 3. The phosphorous cycle is the movement of phosphorus from the environment, to organisms, and back to the environment (not atmosphere because it rarely occurs as a gas).

15. C. The Phosphorous Cycle • 4. Phosphorous may enter soil/water by • Weathering of rocks • Waste from organisms • Decomposing organisms