Answer :
A channel protein functions by carrying ions or molecules across the membrane. It does this by providing a passageway for specific substances to move in or out of the cell. This process occurs through a channel within the protein that allows only certain molecules or ions to pass through based on their size, charge, or other specific properties.
Unlike carrier proteins that undergo shape changes during the transportation of molecules, channel proteins do not change shape while transporting substances. Instead, they act more like selective gates, opening and closing to control the flow of specific molecules or ions across the cell membrane.
In the given options:
- Option a is incorrect because channel proteins do not change shape as they transport molecules.
- Option b is incorrect because channel proteins do not form tiny holes in the membrane; they have specific channels for transportation.
- Option c is correct as it accurately describes the main function of a channel protein.
Therefore, the correct answer to the question is:
c. Carries ions or molecules across the membrane.
