Ecology

Question 1

What are the decomposers? Give examples of decomposers- how can they do this?

Answer 1

decomposers ( bacteria, fungi) breakdown dead animal and plant matter by secreting enzymes into the environment.

The broken down animal/ plant cell move into mineral ions in soil. The plants roots absorb the mineral ions. then the consumers eat those plants and waste materials is released

Question 2

How can decay occur most effectively?

Answer 2

In warm conditions- if it is too cold, chemical reactions will be too slow in microorganisms.
Moist- the moisture makes it easier for the microorganisms to digest in food and prevents them from drying out
Oxygen available- most microorganisms respire aerobically

Question 3

Why is biomass lost as you go up the pyramid-

Answer 3

This biomass is lost due to animals requiring energy for life processes (such as respiration
Some of the material eaten by the consumer is lost as waste.
Energy is used to keep organisms warm

Question 4

How can greenhouse gases help absorb energy?

Answer 4

Energy radiated from the sun reaches the earth, some of the energy is then radiated into the space. Green house gases ( cO2 and methane) help absorb this energy

Question 5

State how eutrophication occurs-

Answer 5

Fertilizers/ unwashed sewage wash up into the rivers.
Increase the concentration of mineral ions (such as nitrates) in the water.
Mineral ions stimulate the growth of algae and plants.
Plants/ algae die due to too much competition of light so they cannot photosynthesize.
Increase in microorganisms which break down dead plant material.
High levels of respiration cause low oxygen levels in the water.
Causing aerobic organisms (fish) to die due to low oxygen levels.