Question

What is the main difference between protein domains and protein subunits? Group of answer choices1. Protein domains do not have secondary structure, whereas protein subunits always have secondary structures 2. Each subunit represents a separate polypeptide chain, while one polypeptide chain may contain several domains 3. Domains are parts of membrane proteins, while subunits are parts of water-soluble proteins 4. Domains are composed mostly of the alpha-helices, while subunits contain both alpha-helices and beta-strands 5. The tertiary structure of domains is stabilized by hydrogen bonds, while the structure of subunits is stabilized by disulfide bonds

Answer 1

Answer: 2. Each subunit represents a separate polypeptide chain, while one polypeptide chain may contain several domains.

Explanation: Each subunit constitutes of one polypeptide chain. A polypeptide chain has one particular gene coding for it. thus it simply implies that a protein must have one gene for each subunit.

Many proteins is made up of different protein domains. A particular domain may appear in a variety of different proteins.

domains are stable on there own, they can be exchanged via genetic engineering between one protein and another.