A food chains shows what eats what in a habitat.
Pyramids of biomass reveal the mass of living material at each stage in a chain. The amount of material and energy decreases from one stage to the next.
Radiation from the sun is the ultimate source of energy for most communities of living things. Green plants and algae absorb some of the suns light energy and transfer this energy into chemical energy.
This happns during photosynthsis and the chemical energy is stored in the substances and then passed onto the consumers who get all the energy and biomass from eating the organisms.
Energy is transferred along food chains from one stage to the next but not all the enrgy avaliable to the organisms at one stage can be absorbed by organisms at the next one.
The amount of avaliable energy decreases from one stage to the next.
- Production of offspring
- Energy released by respiration is used for movement and other life processes -
- Energy is lost in waste materials, such as faeces -
All of the energy use din this way (-) returns to the enviroment and is not avaliable to the next stage in the food chain.
Most food chains are very short, Rarely more than 4 stages as energy is llost at each stage.
Waste Materials from plants and animals
Decay is an essential life process that digests food or waste matter and recycles materials. Materials from living things decay becuase they are digested by microorgansisms.
These microorganisms cause decay by releasing enzymes that break down compounds to be absorbed by their cells
- Bacteria and fungi are the main groups of decomposer
Factors affecting decay
- Amount of avaliable oxygen
Microorganisms are more active and digest materials faster when they are moist in warm and aerobic conditions. They will digest materials more slowly in dry, cold, anaerobic conditions
The Carbon Cycle
All cells contain carbon compounds such as protiens fats and carbohydrates. Carbon is passed from the atmpostphere as carbon dioxide to living things.
- Green plants and algae remove carbon dioxide from the atmostphere by photosynthsis.
- The carbon becomes part of protiens, fats and carbohydrates in the plants and algae
- Orgnisms return carbon dioxide to the atmosphere by respiration.
- (Its not just organisms that repsire, plants/algae/microorgansisms can too)
- Carbon dioxide is also released when fossil fuels such as coal and oil and wood are burned.
- When an animal easts a plant, carbon from the plant becomes part of the fats and protiens in the animal.
- Microorganisms and some animals feed on waste material from animals and the remains of dead animals and plants.
- The carbon then becomes part of these microorganisms and detritus feeders.