B1: Decay and The Carbon Cycle Flashcards
1
Q
How does the process of decay happen?
A
- Plants take in elements like carbon, oxygen, hydrogen and nitrogen from the soil and air. These make up complex compounds that pass through the food chain.
- These elements are returned to the environment in waste products produced by the organisms or when the organisms die.
- These materials decay because they are digested by microorganisms
- All the important elements are returned to the soil, ready to be used by plants and put back into a food chain again.
2
Q
In what conditions do microorganisms work best in?
A
- Warm, moist conditions.
- Microorganisms also break down material faster when there is plenty of oxygen available
3
Q
Why do compost make ideal conditions for microorganisms?
A
- Compost is decayed remains of animal and plant matter that can be used as fertiliser.
- It recycles nutrients back into the soil
- Warm conditions are generated by decomposition so decay is quicker because more microorganisms will be present
- Mesh sides allows air to get in and out so more decay will take place because there will be more microorganisms
4
Q
Explain the carbon cycle.
A
- CO2 is removed by plants and algae to make carbohydrates, fats and proteins.
- Some of the carbon is returned to the atmosphere as CO2 when plants and algae respire
- Some of the carbon becomes part of the fats and proteins in aniamls when plants and algae are eaten
- Some of the carbon is returned to the atmosphere when animals respire
- Detritus feeders and microorganisms feed on remains of dead plants, algae and animals. CO2 returned to atmosphere when they respire.
- Waste produced by animals is also broken down by detritus feeders. Compounds in waster are taken into soil and then into plants as nutrients so carbon is in food chain again.
- Useful plant and animal products (wood and fossil fuels) are burnt. Combustion returns CO2 to atmosphere.
5
Q
What is a detritus feeder?
A
Animals that feed on the waste and remains of animal and plants.
