Ecology.

• What is a habitat?


  The environment in which an organism.
• What is a population?

  A total number of organisms of the same species living in the same geographical area.
• What is a community?

  The populations of all the different species that live in the same habitat.
• A community contains all of the living organisms in an environment.
• What is an ecosystem?

  Both the biotic and abiotic parts of an environment and how they interact with one an other.
• What do plants compete with each other for?

  1. Light.
  2. Space.
  3. Water and mineral ions in the soil.
• What do animals compete with each other for?

  1. Food and water.
  2. Mates.
  3. Territory.
• What is interdependence?


  All different species in a community depend on each other.
• What is a stable community?


  A community where the population remains fairly constant.
• What are biotic factors?

  Living parts of an environment.
• What are abiotic factors?

  Non - living factors of an environment.
• Biotic factors.

  1. Availability of food.
  2. Arrival of a new predator.
  3. Competition between species.
  4. New pathogens.
• Abiotic factors.

  1. Light intensity.
  2. Temperature.
  3. Water.
  4. PH and mineral content of the soil.
  5. Wind intensity and direction.
  6. Oxygen and carbon dioxide.
• How does the carbon cycle start?

  With carbon dioxide in the atmosphere.
• Whats the one way carbon can enter the carbon cycle?

  Photosynthesis.
• In photosynthesis carbon dioxide is combined with water making glucose
• What type of energy does photosynthesis use?

  Light energy
• How does co2 return back to the atmosphere?

  Aerobic respiration.
• Process of the carbon cycle.

  1. Co2 in atmosphere.
  2. Photosynthesis occurs and plants and algae take in carbon dioxide from the atmosphere in photosynthesis.
  3. Plant and algae respire so some of the carbon is released back to the atmosphere as co2.
  4. Animals can eat plants and algae which means co2 is passed on.
• Process of carbon cycle.

  1. Animals respire and some of the co2 is released back into the atmosphere.
  2. Animals release waste products such as faeces and die.
  3. Waste products and remains are broken down into microorganisms such as bacteria or fungi.
  4. These carry out respiration and co2 ends up in the atmosphere again.
• Why are decomposers important?


  They cycle materials through an eco system and release mineral ions into the soil.
• What happens if decomposers can't function effectively?

  Dead remains are slowly concerted to fossil fuels.
• Combusting fossil fuels releases a large amount of co2 into the atmosphere.
• What do gardeners and farmers use compost for?

  A natural fertilizer.
• Why is the rate of decomposition faster at a higher temperature?

  Decomposers use enzymes to break down plant materials and enzymes work faster in warm conditions
• Why do compost heaps tend to be warm?

  Because decomposers release energy when they carry out aerobic respiration.
• What happens if compost gets too hot?

  Enzymes can denature and decomposers can die.
• Why do decomposing microorganisms work faster if the compost is moist?

  Because many chemical reactions in decay require water so gardeners need to ensure compost heats don't dry out.
• Why do decomposers require oxygen?

  Aerobic respiration.
• Why do gardeners mix compost?

  1. To allow more oxygen to pass in the centre.
  2. Breaks up large clumps increasing the surface area for decomposers to act on.
• What happens to decomposition in the absence of oxygen?

  Anaerobic decay which produces a mixture of gases such as methane.
• What do scientists call gases produced by anaerobic decay?


  Biogas.
• What are small scale biogas generators used for?

  To provide fuel for homes.
• Temperature shows geographic variation.
• Where do we find cacti?

  Deserts where water is scarce.
• What does seasonal variation affect?

  The population of a species.
• Abiotic factors are also influenced by human activity.
• What are lichens sensitive to?

  Sulfur dioxide.
• Human activity also affects the levels of gases dissolved in water.
• What is food security?

  Having enough food to feed a population.