Topic 7- Ecology

• What is a habitat?

  place where an organism lives
• What is a population?

  all organisms of one species living in a habitat
• What is a community?

  populations of different species living in a habitat
• What is an abiotic factor?


  non-living factors. of the environment e.g. temperature
• What is a biotic factor?

  living factors of the environment e.g. food
• What is an ecosystem?

  The interaction of a community of living organisms with the non-living parts of their environment
• What do organisms compete for?

  resources to survive and reproduce
• What do plants need to survive?

  light, space, water, and mineral ions from soil
• What do animals need to survive?

  space, food, water and mates
• What do organisms compete with each other+other species for?

  the same resources
• What is interdependence?


  in a community, species depend on other species for food/shelter/pollination/seed dispersal
• What can have far-reaching effects?

  any major change in ecosystem e.g. one species being removed
• What is a stable community?


  species and environmental factors are in balance, so population sizes roughly stay constant
• What is an example of a stable community?

  tropical rainforests and ancient oak woodlands
• What can a change in the environment be?

  increase/decrease in an abiotic or biotic factor
• What can a change in the environment affect?

  sizes of a population in a community
• What can the size of a species population affect?

  population sizes of organisms that depend on them
• What can a decrease in a plant's population do?

  can affect animal species in an environment
• How can a decrease in light intensity/temp/level of CO2 affect plant populations?

  decrease rate of photosynthesis which affect plant growth and a decrease in population size
• How can a decrease in mineral content of soil affect plant populations?

  cause nutrient deficiencies which affect plant growth and decrease in population size
• What are 7 abiotic factors?

  -moisture level

  -light intensity

  -temperature

  -CO2 level

  -wind intensity + direction

  -oxygen level (aquatic animals)

  -soil pH and mineral content
• What are 4 examples of biotic factors?

  -new predators

  -competition

  -new pathogens

  -availability of food
• What is competition?


  one species may outcompete another so that numbers are too low to breed
• What can a change in the environment due to biotic factors affect?

  sizes of populations in a community which can have knock-on effects due to interdependence
• What can a new predator do to an ecosystem?

  cause a decrease in prey population
• What is an adaptation?


  a change in structures or behaviors, often inherited, that improves an organism's ability to survive
• What are structural features?


  features of an organism's body structure e.g. shape or colour
• How have Artic animals (Artic foxes e.g.) adapted?

  white fur to camouflage against the snow
• How does having white fur help Artic animals?


  helps them avoid predators and sneak up on prey
• How have animals that live in cold places (e.g. whales) adapted?

  thick layer of blubber and a low SA:V ratio to help them retain heat
• How have animals that live in hot places (e.g. camels) adapted?

  thin layer of fat and a large SA:V ratio to them lose heat
• Why do many species (e.g. swallows) migrate to warmer climate during winter?

  to avoid problems of living in cold conditions
• How do desert animals conserve water?

  produce very little sweat and small amounts of concentrated urine
• What do brown bears do over winter?

  hibernate
• Why do brown bears lower their metabolism over winter?

  conserves energy -don't need to hunt when there's not much food about
• What are extremophiles (bacteria) adapted to live in?


  very extreme conditions
• Where are 3 examples of where some extremophiles can live?

  -high temperature

  -high salt concentration

  -high pressure
• What are producers?


  produce their own food using energy from the sun
• What are examples of producers?

  green plant or algae
• How do producers make glucose?

  by photosynthesis