7.2 Organisation of an Ecosystem

7.2.3 Decomposition

Keywords: Decompose, Detritivore GCSE Biology Revision "Decomposition"

Decomposer: A decomposer is an organism that breaks down other organisms. Examples include fungi and bacteria.
Detritivore: Detritivores are decomposers that feed on dead organisms. Examples include worms and insects.

Factors Affecting Decomposition

Moisture: Moisture is required for feeding and reproduction.
Oxygen: Oxygen is required for aerobic respiration.
pH/Temperature: The correct pH and temperature is required for enzymes to work at their optimum.

Decay of Milk

- Milk is mixed with an indicator (turns pink).
- When lipase is added, this breaks down the fats in the milk into fatty acids and glycerol.
- The indicator turns yellow to indicate the end of the reaction.
- Repeat until concordant results are obtained.

Uses of Decomposition

Compost

- Gardeners and farmers need optimum conditions so their waste material decays more quickly.
- Compost is a mixture of decomposers and organic matter that is used to improve soil fertility, and is made of this waste.
- This means that recycling of organic waste is done, as new plants can draw minerals from the compost.

Biogas Generators

- Some decomposers can break down material without oxygen (anaerobically).
- This produces methane gas, which is (pretty much) the same thing as natural gas. Natural gas produced in this way is also known as biogas.
- The methane can then either be burned to produce electricity, or used in the natural gas industry.