Living things in their environment

​Learning outcomes

1. Explain the ways in which living things are adapted to their habitats

2. Explain and model food chains, food webs and energy flow

3. Explain the role of decomposers

4. Describe factors affecting the size of populations

5. Describe and investigate some effects of human influences on the environment

Subject | Subject

• study organisms in their environment

• often use sampling techniques - involves finding results for a small, representative part of the area of their study​

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You can try to do your own sampling - Activity 2.3

Ecologist

• shows how energy is transferred between organisms

• made up of many interconnecting food chains​

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Can you make a food web in a rainforest?

Food web

• organisms that get their energy from dead organisms or their waste products

• help to recycle substances from dead organisms and waste so that other living organisms can use them​

What happens if there are no decomposers?

​Decomposer

definition: all the organisms of one species living in the same place (habitat) at the same time

• population increases in size if the number of births per year > the number of deaths per year; and vice versa

• factor affecting population size:

  • food supply

  • number of predators

  • disease​

1. fertiliser added to a lake

2. increased growth of water plants and algae

3. plants underneath die due to lack of sunlight

4. increase in decomposers as more food from dead plants

5. death of fish as little oxygen in the water

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Search: eutrophication

​Pollution

effects of fertiliser pollution in water​

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Main reason:

• using more land to grow crops and farm animals

• building more homes and roads

• cutting trees for firewood and timber

• mining to obtain more minerals from the ground​

Search: habitat destruction in wetlands, rainforests and coral reefs

Habitat destruction

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1. preserving wetlands

2. protecting the ozone layer

3. reducing carbon emissions​

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Search: Ramsar Convention, CFC emission, global warming

​Protecting the environment