Adaptations, interdependence and competition

• Environment


  The conditions that surround the organisms, can be living or non-living
• Habitat


  The place where an organism lives
• Population


  All members of one species that live in a habitat
• Community


  All the populations of different organisms living together
• Ecosystem


  The interaction of a community of living organisms (biotic) with the non-living (abiotic) parts of their environment
• Organism


  A living thing, a type of plant or animal
• Species


  Two organisms that can breed successfully to produce fertile offspring
• Interdependence


  Within a community, each species depends on another species for food, shelter, pollination, seed dispersal etc.
• Stable Community


  One where all the species and environmental factors are in balance so population size remains fairly constant
• Why plants compete for resources

  • Light - required for photosynthesis to produce glucose for energy and growth
  • Space - require space above and below ground to absorb sunlight and water/mineral ions
  • Water - essential for photosynthesis and plant growth
  • Mineral ions - required to make proteins and chlorophyll
• Why animals compete for resources

  • Food - provides energy for growth and reproduction
  • Mates - required for reproduction and passing on genes
  • Territory - provides resources such as food and shelter
• Food web


  Interdependence of organisms, e.g. if earthworm population decreases, grass population increases, frog and mouse populations decrease, sparrow population decreases slightly
• Abiotic factors


  • Light intensity
  • Temperature
  • Moisture levels
  • Soil pH and mineral content
  • Wind intensity and direction
  • Carbon dioxide levels
  • Oxygen levels
• Biotic factors


  • Availability of food
  • New predators
  • New pathogens
  • Competition
• Adaptations to desert regions

  • Kidneys produce concentrated urine to help animal retain water
  • Only active early in morning or late at night when temperature is cooler
  • Structures to increase surface area to volume ratio to aid heat loss e.g. large ears on African Elephant
• Extremophiles


  Animals who live in extreme environments
• Adaptations of deep sea volcanic vents

  • Temperatures very hot, high pressure, no sunlight
• Chemoautotrophs


  Survive by using inorganic chemicals to obtain energy
• Chemoautotrophs


  Other species then use them as a source of nutrition
• Community


  An individual is part of a species but lives in a habitat with different populations that interact in the same environment. The populations are often dependent on each other.
• Ecosystem


  The interaction of the living (biotic) and non-living (abiotic) parts of the environment. Organisms are adapted to the conditions in the ecosystem.
• Interdependence


  • Describes how organisms in a community depend on others for vital services like food, shelter, and reproduction (e.g. pollination, seed dispersal)
• Removal or addition of a species to the community


  Can greatly affect the population of others
• Abiotic factor


  A non-living factor that can affect a community, such as light intensity, temperature, moisture levels, soil pH and mineral content, wind intensity and carbon dioxide levels
• Biotic factor


  A living factor that can affect a community, such as food availability, new predators, new pathogens, and competition
• Adaptations


  • Structural (e.g. shape, colour), behavioural (e.g. playing dead, basking), and functional (e.g. metabolism, water conservation) features that allow organisms to survive in their environment
• Extremophiles


  • Organisms that live in environments with extreme conditions like high temperatures, pressures or salt concentrations
• Adaptations for different environments

  • Cold climates: smaller surface area to volume ratio, more insulation
  • Dry climates: water retention, reduced surface area for evaporation, resting in shade
  • Plant adaptations: reduced leaf area, water storage in stems
• Feeding relationships


  Shown by food chains, starting with producers (photosynthetic organisms) that are eaten by primary consumers, which are then eaten by secondary consumers
• Energy is transferred through organisms in an ecosystem when one is eaten by another