11: The Gut and Digestion
After completing this section, you should know:
- what is meant by the terms: ingestion, digestion, absorption, assimilation, egestion, peristalsis and chyme
- the characteristics, advantages and disadvantages of a herbivorous, carnivorous and omnivorous diet
- the 4 main functions of the gut
- the parts of the gut in the order in which the food passes down it
Plant cells are made of organic molecules using energy from the sun. This process is called photosynthesis. Animals rely on these ready-made organic molecules to supply them with their food. Some animals (herbivores) eat plants; some (carnivores) eat the herbivores.
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- 11.1: Herbivores
- Herbivores eat plant material. While no animal produces the digestive enzymes to break down the large cellulose molecules in the plant cell walls, micro-organisms' like bacteria, on the other hand, can break them down. Therefore herbivores employ micro-organisms to do the job for them.
Thumbnail: Illustration of human gastrointestinal tract. (Public Domain; Indolences ).