geography AQA gcse: living world

• what is an ecosystem?

  An ecosystem is a system in which organisms interact with eachother and with there environment
• what are the two components of an ecosystem?

  Abiotic and Biotic
• what does abiotic mean?

  these are non-living, such as air, water, heat and rock
• what does biotic mean?

  these are living organisms such as plants, insects and animals
• what are the two types of biotic components

  flora: plant life occurring in a particular region or time

  fauna: animal life of any particular region or time
• what are food chains?

  useful in explaining the basic principles behind ecosystems. They show only one species at a particular trophic level
• what are food webs?

  consist of a network of many food chains interconnected together
• what is the nutrient cycle?


  plants take in nutrients to build into new organic matter. Nutrients are taken up when animal eat plants and then returned to the soil when animals die and the body is broken down by decomposers
• what is ‘litter’ in the context of nutrients cycle?

  this is the surface layer of vegetation, which over time breaks down to become human
• what is ‘biomass’ in the context of the nutrients cycle?

  the total mass of living organisms per unit area
• what is a biome?


  a biome is a large geographical area of distinctive plant and animal groups, which are adapted to that particular enviroment
• what are the four different biomes?

  tropical rainforest, hot desert, temperate forest, tundra
• what are the: location, temperature, rainfall, flora and fauna like in the tropical rainforest?


  location: centred along the equator

  temperature: hot all year (25°-30°C)

  rainfall: very high (over 200mm/yr)

  flora: tall trees forming canopy; wide variety of species

  fauna: greatest range of different animal species. most live in canopy layer
• what are the: location, temperature, rainfall, flora and fauna like in the hot desert?


  location: found along the tropics of cancer and capricorn

  temperature: hot by day (over 30°C) cold by night

  rainfall: very low (below 300mm/yr)

  flora: lack of plants and few species; adapted to drought

  fauna: many plants are small and nocturnal: except for camel
• what are the: location, temperature, rainfall, flora and fauna like in the temperate forest?

  location: between latitude 40°-60° north of the equator

  temperature: warmer summers and mild winters (5°-20°C)

  rainfall: variable rainfall (500-1500m/year)

  flora: mainly deciduous trees; a variety of species

  fauna: animals adapt to colder and warmer climates. some migrate
• what are the: location, temperature, rainfall, flora and fauna like in the tundra?

  location: far latitudes of 65° north and south of the equator

  temperature: cold winters and cool summers (below 10°)

  rainfall: low rainfall(below 500mm/year)

  flora: small plants grow close to the ground and only in summer

  fauna: low numbers of species. most animals found along coast
• how much (%) of the earths surface does the rainforest cover?

  2%
• how many of the worlds plants are animals does the rainforests hold?

  over half
• what is the rainforests interdependance like?


  a rainforest works through interdependance. this is where the plants and animals depend on each other for survival
• describe the distribution of tropical rainforest?

  tropical rainforests are centered along the equator