Section 4 Flashcards
What is a population?
all organisms of the same species found in the same ecosystem
What is a community?
All the different populations living in a particular area.
What is a habitat?
A specific place where an organism lives.
What is an ecosystem?
A community of organisms that interact and depend on each other, plus all the abiotic and biotic factors in the area
What are biotic factors?
What are abiotic factors?
Biotic factors are living organisms that affect the environment.
Abiotic factors are physical factors that affect the environment.
What is a producer?
A green plant, it can produce its own food by photosynthesis. It is ALWAYS at the beginning of the food chain.
What is a primary consumer?
An animal that eats plants (producers)
What is a secondary consumer?
An animal that eats other animals (primary consumers)
What is a tertiary consumer?
An animal that feeds on secondary consumers
What is a decomposer?
An organism that feeds on dead or decaying matter. Can be anywhere in the food chain e.g. fungi and bacteria
What are the steps of eutrophication?
- Farmers add too much inorganic fertilisers e.g. nitrates and phosphates to the soil
- These fertilisers are easily leached and can enter rivers and lakes.
- The nitrate levels in the lakes and rivers increase.
- The algae uses the nitrate levels to grow until there is an overgrowth of algae called algae growth.
- The algae block the light from reaching the water plants and so these plants die because they cannot photosynthesis.
- When the algae die, they decay at the bottom of the lake.
- The bacteria multiply hugely by feeding on the algae making them decay.
- The bacteria uses up a lot of the oxygen in the lake as they respire.
- There is not enough oxygen left in the lake for water animals.
- So water animals like fish die.
- This process of polluted water is called eutrophication.
