Topic B13b - Interdependence, Pollution & Cycles Flashcards
(18 cards)
Define producers.
They are organisms which make their own food. (E.g. Green plants use photosynthesis)
What are primary consumers?
Animals or organisms which eat plants (eat producers)
What are secondary consumers?
Animals or organisms which eat primary consumers
What do food chains do?
They show you what eats what
What is a tropic level?
Where organisms that feed at the same level in a food chain.
Define interdependent
Organisms in an area depending on each other for food
Name 2 ways in which animals release energy
Respiration and some transferred into biomass (substance that form tissues).
Hat determines the shape of a biomass pyramid
The energy transferred at each tropic level
What is parasitism?
A feeding relationship in which 2 organisms live together with one feeding off the other.
Name 2 examples of parasites
Headlice and fleas
Explain mutualism
Where organisms live in close relationships where both organism benefit.
What does nitrogen fixing bacteria do?
Bacteria that can turn nitrogen in the air into nitrogen compounds.
What is chemosynthetic bacteria
Are producers that get their energy from chemical substances rather than light.
Explain how the increase in population can affect the amount of pollution.
The more people there are, the more water we need and food production. Crops are grown better with fertiliser (which contains nitrates and phosphates)
Explain how fossil fuels can add to the pollution in the atmosphere.
When we burn fossil fuels, sulphur dioxide is released from and pollutes the air if the concentration is high
How can farmers damage the environment?
If farmers use too much fertiliser, rain washes it away. It can get into the water and raise the natural concentration or nitrates and phosphates. This is called eutrophication.
Explain how aquatic animals may die due to farmers.
1) fertiliser is added
2) heavy rain washed fertiliser off and nitrates and phosphates dissolve in water.
3) nitrates and phosphates not taken up by plants and washed into streams and rivers
4) high nitrate and phosphate concentrations in the water encourage plants and algae to grow rapidly
5) surface plants block sunlight so plants underneath die and stop photosynthesis
6) bacteria that break down dead materials increase numbers and use up more oxygen from water
7) oxygen concentration in water decreases
8) animals die due to lack of oxygen
Explain how indicator species detects the amount of pollution in an area.
Some organisms are so sensitive to polluting chemicals that when exposed to sulphur dioxide they get killed. This means when they are exposed to sulphur dioxide, the less there are.
