Biology, 12: Organisms and their environment

• Food chain shows transfer of energy from one organism to the next
• Food web is a network of interconnected food chains
• Producers are organisms that makes its own organic nutrient using energy from the Sun through photosynthesis
• Consumers are organisms getting it energy by feeding on other organisms
• Herbivores are organisms that gets its energy by eating plants
• Carnivores are organisms that getting its energy by eating other animals
• Decomposers are organisms that gets its energy from dead or waste organic matter
• Ecosystem is a unit containing all organisms and their environment, interacting together, in a given area
• The trophic level is the position of an organism in a food chain or food web
• Energy can be lost in animal due to:

  • Producing new tissues or gametes for reproduction
  • Respiring
  • Excretion
• Only 10% of energy is transferred between trophic levels
• Top organisms waste more energy hunting for food than from eating it