What are the components of the cell membrane according to the fluid mosaic model?

• A. Phospholipids, cholesterol, proteins, and carbohydrates
• B. Phosphates, cholesterol, water, and proteins
• C. Carbohydrates, proteins, and nucleic acids
• D. Fatty acids, proteins, enzymes, and nucleic acids

Answer: (A)

The fluid mosaic model of the cell membrane describes its structure as a dynamic and flexible arrangement of various components. The correct response identifies phospholipids, cholesterol, proteins, and carbohydrates as the main constituents of the cell membrane.

Phospholipids form the fundamental bilayer of the membrane, creating a hydrophobic core that separates the internal environment of the cell from the external surroundings. This bilayer allows the membrane to maintain fluidity and flexibility while providing a semi-permeable barrier.

Cholesterol is interspersed within the phospholipid bilayer and plays a critical role in modulating membrane fluidity across various temperatures. It helps stabilize the membrane structure, making it less permeable to very small water-soluble molecules that might otherwise pass freely through.

Proteins embedded within the membrane serve numerous functions, including transport, signaling, and structural support. These integral and peripheral proteins can move laterally within the membrane, contributing to the "fluid" aspect of the fluid mosaic model.

Carbohydrates are often attached to these proteins and lipids, forming glycoproteins and glycolipids. They are involved in cell recognition and signaling, allowing cells to communicate and interact with their environment.

This answer encapsulates the comprehensive composition of the cell