Question

ASAP You are observing proteins in a lab for an experiment. During transport, they have started to unwind and lose their shape. You notice long strands wound into alpha helices. What level of structure are the proteins in? A. Quaternary B. Primary C. Secondary D. Tertiary

Answer 1

Answer:

C. Secondary

Explanation:

In proteins, the structure of local segments can be arranged into three different three-dimensional formations: alpha helices (α-helix), beta sheets (β-strand) and omega loops. An alpha helix is the most common secondary protein conformation because it has low-energy and a stable arrangement. The α-helix is formed by the interaction between amino acids of every backbone N−H hydrogen bonded with the backbone C=O group of the corresponding amino acid residue in the polypeptide chain. The α-helix motif is very common in transmembrane segments of proteins that cross the lipid bilayer.