Write two functions of waxes.

Explanation

### Step-by-Step Solution:

1. **Definition of Waxes**: Waxes are long-chain non-polar lipids. They are composed of long hydrocarbon chains and are typically hydrophobic (water-repelling).

2. **Chemical Composition**: Waxes are formed through ester bonds between fatty acids and alcohol. The general structure of an ester bond can be represented as R-C(=O)-O-R', where R is a hydrocarbon chain from the fatty acid and R' is from the alcohol.

3. **Function 1 - Protective Layer**: One of the primary functions of waxes is to form a protective layer on the surfaces of plants, particularly on leaves. This layer, known as the cuticle, helps to prevent water loss by reducing evaporation, thus aiding in water retention in plants.

...