Instructions
Read the information below regarding fatty acids, triglycerides, and phospholipids. Then, complete the exercises following each section.
1. Fatty Acids
Fatty acids are carboxylic acids with long hydrocarbon chains. They can be classified as saturated or unsaturated:
- Saturated fatty acids: These contain no double bonds between carbon atoms, meaning they are saturated with hydrogen atoms. For example, stearic acid has the formula C18H36O2.
- Unsaturated fatty acids: These contain one or more double bonds between carbon atoms. For example, oleic acid has one double bond and its formula is C18H34O2.
Fatty acids primarily consist of carbon (C), hydrogen (H), and oxygen (O) atoms.
2. Triglycerides
Triglycerides are formed by the esterification of three fatty acid molecules to one glycerol molecule. The general formula is R1COOH + R2COOH + R3COOH + C3H8O3 → C3H5(O2R)3 + 3H2O. Triglycerides store energy in fat cells and consist of carbon, hydrogen, and oxygen atoms as well.
3. Phospholipids
Phospholipids are major components of cell membranes and consist of two fatty acids, a glycerol molecule, and a phosphate group. The general structure can be represented as follows:
Fatty Acid - Fatty Acid - Glycerol - Phosphate group
Phospholipids contain carbon (C), hydrogen (H), oxygen (O), and phosphorus (P) atoms. Their unique structure allows them to form lipid bilayers in cell membranes.
4. Summary Exercise
Summarize the key differences between saturated and unsaturated fatty acids, and describe the structure of triglycerides and phospholipids. Include the atoms and molecules involved in each.