In the Photosynthetic Archaean Halobacterium Halobium, a Membrane Transport Protein

question 43

Multiple Choice

In the photosynthetic archaean Halobacterium halobium, a membrane transport protein called bacteriorhodopsin captures energy from sunlight and uses it to pump protons out of the cell.The resulting proton gradient serves as an energy store that can later be tapped to generate ATP.Which statement best describes how bacteriorhodopsin operates?

• A)The absorption of sunlight triggers a contraction of the β barrel that acts as the protein's central channel, squeezing a proton out of the cell.
• B)The absorption of sunlight triggers a shift in the conformation of the protein's seven, membrane-spanning α helices, allowing a proton to leave the cell.
• C)The absorption of sunlight triggers a restructuring of bacteriorhodopsin's otherwise unstructured core to form the channel through which a proton can exit the cell.
• D)The absorption of sunlight triggers the activation of an enzyme that generates ATP.

---

Definitions:

One-Time Sales

Refers to transactions where products or services are sold on a singular occasion, rather than on a recurring basis.

Individual Customers

Single persons or entities that purchase goods or services for personal use or consumption rather than for resale.

Trade Associations

Organizations founded and funded by businesses that operate in a specific industry, aimed at promoting their collective interests.

Commercial Banks

Commercial banks are financial institutions that offer a wide range of banking services to businesses and individuals, including deposit accounts, loans, and other financial products.