8.4. RELATIONSHIP BETWEEN AUTOTROPHS AND HETEROTROPHS

YouTube: DesertUSA "Desert food chain"

Remember:

• Autotrophs combine inorganic matter (water, mineral salts and CO2) with energy from the Sun (photosynthesis) or from chemical reactions (chemosynthesis) to produce their own organic compounds. Plants, algae and some bacteria are autotrophs.
• Heterotrophs take organic matter made by other living things. Animals, fungi, protozoa and some bacteria are heterotrophs. According to the type of food they eat, the heterotrophic organisms are classified into:
  • Herbivores: they eat plants (e.g. cows)
  • Carnivores: they eat meat (e.g. lions)
  • Omnivores: they eat meat and plants (e.g. humans)
  • Saprophytes: they eat decaying organic matter (e.g. fungi).