Digestion is the process through which our food goes when we eat. In this biology lesson , digestion is explained in detail. The parts of our body that help digestion are described, what is involved in digestion is explained etc. Thanks to graphs, GCSE students will be able to understand this notion better.
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Your digestive system (the gut) - your inner tube
- What is digestion ?
Digestion is the breakdown of large, insoluble food molecules into small, soluble food molecules so that they can be absorbed into the bloodstream. Large food molecules like proteins must be broken down into small amino acids. [...]
- Enzymes involved in digestion
The gut is your digestive system and is approximately 9 meters long. It begins at your mouth and ends at your anus. It bends and twists a lot to enable itself to fit inside your body. It is made up of many different parts.
The mouth is where it all begins. Here, you ingest food and drink into your body. Food enters in bite-sized chunks and is chewed. Chewing food mixes it with saliva, which is produced in your salivary glands. [...]
The oesophagus passes food down to your stomach. The oesophagus contains circular muscles in its wall, which contract and squeeze in behind the food to push it along. This motion of food travelling down your gut is called peristalsis. [...]
The stomach is a muscular bag that can hold up to two litres of food. The stomach makes digestive juices, these contain: [...]
The small intestine
The small intestine first of all, is not very small! It is about 6 meters in length. Three important liquids are added here to the liquid food now in your intestine. [...]
The small intestine has another very important job besides from digestion, and that is to absorb the digested food through the wall of the small intestine, into the blood. The small intestine is well designed for this, it has: [...]
The large intestine
By the time your food reaches the large intestine, it is mainly just fibre, dead cells, bacteria and water. Here, some of the water passes back into the blood and the solid waste (faeces) is stored in the rectum. [...]