Question

List four components of a plasma membrane and explain their function.

a) Proteins, lipids, carbohydrates, and water; involved in structural support.
b) Phospholipids, cholesterol, proteins, and carbohydrates; contribute to selective permeability.
c) Nucleic acids, enzymes, water, and ions; responsible for energy production.
d) Carbohydrates, nucleotides, amino acids, and lipids; critical for DNA replication.

Answer 1

The plasma membrane consists of phospholipids, cholesterol, proteins, and carbohydrates, which collectively maintain its structure, fluidity, and selective permeability, while facilitating communication and cell recognition.

Step-by-step explanation:

The four principal components of a plasma membrane and their functions are:

• Phospholipids: Form the fluid bilayer that is the basic structure of the membrane.
• Cholesterol: Embedded within the bilayer to provide flexibility and maintain the fluidity of the membrane.
• Proteins (integral and peripheral): Integral proteins span the membrane and are involved in transport and communication, whereas peripheral proteins are involved in signaling and maintain the cell's structure.
• Carbohydrates: Attached to proteins and lipids on the membrane's exterior, these molecules are involved in cell recognition and adhesion.

Their collective functions are critical for maintaining the selective permeability of the membrane, facilitating cell communication, and ensuring the integrity and flexibility of the cell membrane.