Biology – 4.1 Biological molecules | e-Consult

Fats, also known as lipids, are primarily composed of carbon (C), hydrogen (H), and oxygen (O). However, the proportion of oxygen is significantly lower than in carbohydrates. The arrangement of atoms in fats is crucial. Fats are composed of glycerol and fatty acids. Fatty acids consist of a long hydrocarbon chain (primarily C and H) with a carboxyl group (-COOH). The hydrocarbon chains can be saturated (only C-H bonds) or unsaturated (containing C=C double bonds). The presence of C-H bonds contributes to the hydrophobic (water-repelling) nature of fats, while the arrangement of the hydrocarbon chains influences their physical state (solid or liquid) at room temperature. Saturated fats tend to be solid due to their straight chains packing tightly, while unsaturated fats are often liquid due to their kinks preventing tight packing.