Chapter 21, Problem 37A

Interpretation Introduction

Interpretation:

The circumstances for classification of biomolecules as lipid must be explained. Whether the classification is based on any particular characteristic structure or on some physical property must also be explained.

Concept Introduction:

Lipids are biomolecules which are generally triester of glycerol with long chain carboxylic acids known as Fatty acids.

Answer to Problem 37A

Lipids are biomolecules which are water insoluble. These include fats, phospholipids waxes and steroids.

The classification is based on some physical property.

Explanation of Solution

Lipids are water insoluble and thus easily can be extracted from cells with organic solvents like benzene. Based on molecular structure there are mainly four types of lipids. These are fats, phospholipids waxes and steroids.

Fats are most common among all lipids. These are triester of glycerol with long chain carboxylic acids like oleic acid, stearic acid, palmitic acid etc. These acids are termed as Fatty acids. Steroids are lipids which have fused polycyclic ring structure. One of the most common steroids is cholesterol.