Why are proteins sometimes called workhouse molecules?

Why are proteins sometimes called workhouse molecules?

• A. Proteins store genetic information.
• B. Proteins carry out almost all cell processes and form cell structures.
• C. Proteins provide the primary energy source for cells.
• D. Proteins are only involved in immune responses.

Answer: (B)

Proteins are workhorse molecules because they perform most tasks a cell needs to stay alive and function. They make up the vast machinery of the cell: enzymes catalyze virtually all chemical reactions, structural proteins give shape and support to cellular components, transport proteins move molecules across membranes, and signaling proteins transmit information to coordinate activities. Antibodies and other immune proteins also defend the organism, but the scope of protein roles goes far beyond immunity, touching almost every process necessary for life. Storing genetic information is the job of DNA (and, for some roles, RNA), not proteins. Proteins aren’t the primary energy source for cells; carbohydrates and fats supply most energy, with proteins used mainly for building, repair, and function unless energy must be derived from them in starvation. And while proteins participate in immune responses, saying they’re only involved in immunity ignores their many other essential functions.

Proteins are workhorse molecules because they perform most tasks a cell needs to stay alive and function. They make up the vast machinery of the cell: enzymes catalyze virtually all chemical reactions, structural proteins give shape and support to cellular components, transport proteins move molecules across membranes, and signaling proteins transmit information to coordinate activities. Antibodies and other immune proteins also defend the organism, but the scope of protein roles goes far beyond immunity, touching almost every process necessary for life.

Storing genetic information is the job of DNA (and, for some roles, RNA), not proteins. Proteins aren’t the primary energy source for cells; carbohydrates and fats supply most energy, with proteins used mainly for building, repair, and function unless energy must be derived from them in starvation. And while proteins participate in immune responses, saying they’re only involved in immunity ignores their many other essential functions.