Which of the following best defines a domain?
A) A supersecondary region, often shared by proteins, that has a specific function.
B) A repetitive supersecondary structure.
C) A double-layered arrangement formed so that the polar groups face the aqueous environment, while the nonpolar regions are kept away from the aqueous environment.
D) An unfolded region of a protein.

Question

Quizplus · Accepted Answer

A domain in the context of protein structure refers to a distinct structural unit within a protein that can often fold independently of the rest of the protein chain and usually has a specific function. This definition aligns with choice A, indicating a region within proteins that is not only structurally distinct but also functionally significant. Choices B, C, and D describe other structural features or arrangements that do not accurately define a domain.

Which of the Following Best Defines a Domain