How do vesicles move through the cell during the process of protein secretion?

• A. By being pushed by the flow of cytoplasmic fluid
• B. By passive diffusion through the cytoplasm
• C. By being transported along microtubules by motor proteins
• D. By floating freely in the cytosol

Answer: (C)

Verified step by step guidance

1. Understand that vesicles are small membrane-bound sacs that transport substances within a cell.
2. Recognize that the process of protein secretion involves the movement of vesicles from the endoplasmic reticulum to the Golgi apparatus and then to the cell membrane.
3. Learn that vesicles do not move by passive diffusion or by being pushed by cytoplasmic fluid, as these methods are inefficient for directed transport.
4. Identify that vesicles are transported along microtubules, which are part of the cell's cytoskeleton, providing a track for movement.
5. Know that motor proteins, such as kinesin and dynein, attach to vesicles and 'walk' along microtubules, using energy from ATP to transport vesicles to their destination.