Biological Molecules & Enzymes

What this lesson covers

Biological Molecules & Enzymes is a 7-part O Level 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, names the mistakes that cost marks in an exam, ends with a recap of what to remember.

How it begins

Carbohydrates contain carbon, hydrogen and oxygen. Built from simple sugars such as glucose; many glucose molecules joined make starch (plant storage), glycogen (animal storage) and cellulose (plant cell walls). Fats and oils contain the same three elements but proportionally far less oxygen. Built from fatty acids and glycerol: three fatty acids to one glycerol.

The 7 parts

1. The molecules and their building blocks
2. The four food tests
3. Enzymes: what they are and how they work
4. The two graphs, and what each half means
5. Where marks go
6. What to remember
7. Watch one worked through