Carbohydrates are not lipids. Lipids are a diverse group of organic compounds that include fats, oils, waxes, and phospholipids.

Lipids provide structural support to cell membranes by forming a hydrophobic barrier that prevents the passage of water-soluble molecules.

Phospholipids are the major lipids found in animal cell membranes. They consist of a glycerol backbone, two fatty acid chains, and a phosphate group.

Cholesterol plays multiple roles in cell membranes. It increases membrane fluidity, stabilizes membrane structure, and regulates membrane permeability.

Testosterone, estrogen, and progesterone are all types of steroid lipids. They are involved in various physiological processes, including reproduction, growth, and development.

Triglycerides are the main form of energy storage in the body. They are composed of three fatty acid chains attached to a glycerol backbone.

Waxes are a type of lipid commonly found in plant cell walls. They provide a protective coating that helps prevent water loss and infection.

Lipids play multiple roles in hormone production. They serve as precursors for hormone synthesis, regulate hormone release, and transport hormones throughout the body.

Phosphatidylcholine is an example of a phospholipid. It is a major component of cell membranes and plays a crucial role in maintaining membrane structure and function.

Lipids play multiple roles in cellular signaling. They transmit signals between cells, regulate gene expression, and activate enzymes.

Phospholipids are the major lipids found in nerve cell membranes. They contribute to the electrical properties of nerve cells and play a role in nerve impulse transmission.

Lipids play multiple roles in the liver. They are involved in energy storage, detoxification, and protein synthesis.

Waxes are a type of lipid commonly found in the outer layer of the skin. They provide a protective barrier that helps prevent water loss and infection.

Lipids play multiple roles in fat-soluble vitamin absorption. They aid in the absorption of fat-soluble vitamins, regulate their release, and transport them throughout the body.

Oleic acid is an example of an unsaturated fatty acid. It is a monounsaturated fatty acid, meaning it has one double bond between carbon atoms in its hydrocarbon chain.