Theory question 105
Ecosystem and Ecological Factors(a) What is an ecosystem?
(b) Name two abiotic factors each which affect plants and animals in a terrestrial habitat.
(c) Describe the effects of three abiotic factors on a named plant and an animal in the habitat mentioned in (b) above.
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(a) An ecosystem is a natural unit made up of a community of living organisms interacting with one another and with their non-living environment.
(b) Any two for each: temperature; rainfall/water; light; wind; relative humidity; soil (edaphic) factors such as pH and texture; topography.
(c) Name a plant and an animal (e.g. maize and the grasshopper/lizard) and give three factors, e.g. Temperature: high temperature increases transpiration and may wilt the plant; animals become more active up to a point, very high heat makes them seek shade or aestivate. Rainfall/water: enough rain allows germination and growth; drought causes wilting/death; animals need water and breed in the rainy season. Light: plants need light for photosynthesis and flowering; animals use light for vision and their activity follows day length (e.g. lizards bask in sunlight). Wind: spreads pollen and seeds and increases transpiration; may damage plants; affects flight of insects.
Always name the plant and animal you are describing.