Nutrition in Humans

What this lesson covers

Nutrition in Humans is a 8-part Class 9 Biology lesson. Each part makes one point and then hands over to the next, so it can be read in a sitting or picked up again at the part you stopped on. It defines the idea in plain words before using it, works through an example step by step, breaks the topic into its parts and compares them, shows where it is used outside the textbook, names the mistakes that cost marks in an exam, ends with a recap of what to remember.

How it begins

Digestion breaks large insoluble food molecules into small soluble ones that can be absorbed into the blood. A starch molecule is far too big to cross the gut wall. Broken into glucose, it passes easily. That is the entire purpose of the digestive system. Two kinds happen together: Mechanical, teeth chewing, stomach churning. Increases surface area. Chemical: enzymes breaking bonds.

The 8 parts

1. Why food must be digested
2. The journey
3. The enzymes
4. Why the small intestine is shaped as it is
5. Health and the gut
6. Where marks get lost
7. What to remember
8. Watch one worked through