Questions: Question 57 What protein provides flexibility and strength to connective tissues? keratin myosin actin collagen fibrinogen

The answer is the fourth one (D): collagen.

Explanation for each option:

• Keratin: This is a structural protein found in hair, nails, and the outer layer of skin. It provides strength and protection to these tissues but is not primarily involved in the flexibility and strength of connective tissues.

• Myosin: This is a motor protein involved in muscle contraction and is not a component of connective tissues.

• Actin: This is another protein involved in muscle contraction and cellular movement. While it is important for cell structure and movement, it is not the primary protein providing strength and flexibility to connective tissues.

• Collagen: This is the correct answer. Collagen is the main structural protein in the extracellular space in various connective tissues. It provides tensile strength and flexibility, making it essential for the integrity of skin, tendons, ligaments, and other connective tissues.

• Fibrinogen: This is a blood plasma protein that's converted into fibrin during blood clotting. It is not involved in providing flexibility and strength to connective tissues.

In summary, collagen is the protein that provides flexibility and strength to connective tissues.