Decay and Nutrient Cycles Flashcards
Why is decay a good thing
Waste materials and dead bodies are broken down and do not build up in the environment
The nutrients in the waste material and dead bodies are released back into the environment
What is decay
The breakdown of material through the action of microorganisms (bacteria and fungi)
Why is decay inconvenient
The microorganisms use up a lot of oxygen and produce carbon dioxide because they respire
Decay of food can be dangerous for humans
What is released by decay
Carbon
Nitrogen
Phosphorus
What is needed for decay
Water - microbes need water to survive
Oxygen - decomposing microbes are aerobic and need a lot of oxygen for respiration
Warmth - the decomposers enzymes work slowly when it is cold and are denatured when it is hot
What foods can’t microorganisms decay
Dried (no water for decomposers)
Canned (no oxygen so decomposers are unable to respire)
Frozen (to cold for decomposers enzymes to work efficiently)
Treated with substances (stops the growth of microbes e.g salt, sugar, vinegar, smoke)
Give some uses of decay
Sewage works
Compost heaps
What is the carbon cycle
A cycle in which carbon is recycled for survival on earth
What are the processes of the carbon cycle
Photosynthesis in which green plants extract carbon dioxide from the air and convert it into glucose
Respiration which releases the carbon dioxide back into the air
Feeding which Is the way in which the carbon gets from plants to animals
Death which provides materials for microorganisms to feed on
Decay which involves respiration by bacteria and fungi
What releases a lot of carbon dioxide into the atmosphere
Burning fossil fuels
Explain the importance of nitrogen
It is a visual element for all living things it is needed to make proteins which are used for the building and reaping of cells
What does the nitrogen cycle depend on
The activity of various bacteria
How do animals get nitrogen
By eating plant proteins
In decomposition body proteins and urea are converted to what
Ammonia
