Question

Which statement describes processes of receptor-mediated endocytosis, exocytosis, and the changes in the membrane organization involved with each?

a) Receptor-mediated endocytosis involves the export of substances, while exocytosis imports molecules.
b) Receptor-mediated endocytosis and exocytosis both involve the movement of substances into and out of the cell.
c) Changes in membrane organization occur only during receptor-mediated endocytosis.
d) Exocytosis exclusively occurs in plant cells.

Answer 1

Receptor-mediated endocytosis involves internalizing molecules via clathrin-coated vesicles, while exocytosis involves exporting substances from the cell by fusing vesicles with the plasma membrane.

Step-by-step explanation:

The correct statement that describes the processes of receptor-mediated endocytosis, exocytosis, and the changes in the membrane organization is that both processes involve the movement of substances into and out of the cell, with specific mechanisms to handle these transactions.

Receptor-mediated endocytosis is a form of active transport where cells internalize molecules (such as proteins) by the inward budding of plasma membrane vesicles containing proteins with receptor sites specific to the molecules being internalized. This process usually involves a specific area of the cell membrane that contains clathrin-coated pits. These pits invaginate and engulf the substance, and then pinch off to form a vesicle within the cell, bringing the substance into the cell's interior.

Exocytosis, on the other hand, is an active transport process by which a cell directs the contents of secretory vesicles out of the cell membrane and into the extracellular space. This process usually involves vesicles moving towards the plasma membrane, fusing with it, and then releasing their contents to the cell's exterior.