Use the Following Information When Answering the Corresponding Questions)

Use the following information when answering the corresponding questions) .
Rhodopsins are light- sensitive molecules composed of a protein opsin) and retinal derivative of vitamin A) . Opsin is a membrane protein with several a- helical segments that loop back and forth through the plasma membrane. There are two classes of rhodopsins. According to Oded Beje, one class has relatively slow dynamics a photocycle of approximately 0.5 second) and is well suited for light detection. The second class has faster dynamics a photocycle of approximately 0.02 seconds) and is well suited for chemiosmosis-pumping of protons or chloride ions across cell membranes. Oded Beje was the first, in September 2000, to report on a rhodopsin proteorhodopsin) found in the domain Bacteria. [
-Proteorhodopsin consists of a single polypeptide chain. What is the highest level of structure found in this protein?

A) primary
B) quaternary
C) secondary
D) tertiary