Which of the following does NOT contain a structural protein?

• A. Hair
• B. Tendons
• C. Spider silk
• D. Egg white

Answer: (D)

Verified step by step guidance

1. Step 1: Understand the concept of structural proteins. Structural proteins are responsible for providing support, strength, and shape to cells and tissues. Examples include keratin (found in hair), collagen (found in tendons), and fibroin (found in spider silk).
2. Step 2: Analyze the options provided. Hair contains keratin, a structural protein. Tendons contain collagen, another structural protein. Spider silk contains fibroin, which is also a structural protein.
3. Step 3: Consider the composition of egg white. Egg white primarily contains albumin, which is a globular protein involved in storage and transport, not a structural protein.
4. Step 4: Compare the functions of the proteins in the options. Structural proteins are distinct from globular proteins like albumin, which are not involved in providing structural support.
5. Step 5: Conclude that egg white does NOT contain a structural protein, as its primary protein (albumin) serves a different biological function.