Trophic levels

• What are trophic levels?

  Different levels within a food chain
• What type of organisms are found at the first trophic level?

  Producers like plants or algae
• Why are producers called producers?

  They use photosynthesis to produce food
• What do primary consumers eat?

  Plants and algae
• What are secondary consumers also known as?

  Carnivores
• What does the term tertiary consumers refer to?

  Third level of consumers in the chain
• Why are there usually no more than four or five trophic levels?

  Energy gets lost at each level
• What percentage of energy is passed to the next trophic level?

  About 10 percent
• If trophic level 1 has 1,000 joules, how much energy is in trophic level 2?

  100 joules
• If trophic level 3 has 10 joules, how much energy is in trophic level 4?

  1 joule
• What are apex predators?

  Carnivores with no predators
• Where do omnivores fit in the trophic levels?

  Generally in trophic level 3
• What role do decomposers play in the ecosystem?

  They recycle nutrients from dead matter
• What are the main groups of organisms in a food chain?

  • Producers (plants, algae)
  • Primary consumers (herbivores)
  • Secondary consumers (carnivores)
  • Tertiary consumers (carnivores)
  • Apex predators (top carnivores)
  • Omnivores (eat both plants and animals)
  • Decomposers (bacteria, fungi, worms)
• What is the energy transfer in trophic levels?

  • Trophic level 1: 1,000 joules
  • Trophic level 2: 100 joules
  • Trophic level 3: 10 joules
  • Trophic level 4: 1 joule
  • Only about 10% energy transfer