Chapter 7 - Biogeochemical cycles

Question 1

What is a Biogeochemical cycle ?

Answer 1

Processes moving elements between biosphere, atmosphere, hydrosphere, and lithosphere

Question 2

what are the main processes of the carbon cycle ?

Answer 2

1. Photosynthesis converts CO2 and water into carbohydrates, proteins, and lipids, storing carbon in the biosphere.
2. Respiration releases energy captured in photosynthesis, with aerobic respiration returning carbon as CO2 to the atmosphere and anaerobic respiration producing methane.
3. Food webs depict the transfer of carbohydrates, proteins, and lipids through plant-herbivore-carnivore interactions.
4. Fossilization and combustion contribute to long-term carbon storage and the release of carbon dioxide, respectively.

Question 3

what are some of the human impacts on the carbon cycle ?

Answer 3

• Changes in photosynthesis
• Changes in aerobic respiration
• Changes in anaerobic respiration
• carbonic acid concentrations in the sea
• Hydrocarbon fuel extraction and burning
• Farming practices
• Urbanisation

Question 4

Explain some ways that humans impact on the carbon cycle

Answer 4

• deforestation reduces movement of carbon from the atmosphere into biomass
• afforestation increases the movement of carbon from the atmosphere into biomass