Question

cells import and export materials through vesicular transport. vesicular transport is an active transport process, and thus it requires the expenditure of energy. in a vesicular transport process called exocytosis, cellular products from the endoplasmic reticulum and golgi apparatus are first packaged into membrane - bound secretory vesicles. the vesicles move to the membrane and fuse with it, causing the release of the packaged cellular products into the extracellular environment. endocytosis is the vesicular movement of material in the opposite direction—into the cell. three types of endocytosis exist: phagocytosis, pinocytosis, and receptor - mediated endocytosis. phagocytosis is useful for large particles and is referred to as \cell eating.\ pinocytosis allows the cell to ingest extracellular fluid and its solutes, so it is nicknamed \cell drinking.\ receptor - mediated endocytosis involves cell surface receptors specifically binding an external substance, which initiates its ingestion. this is the most specific type of phagocytosis because receptors are involved. in all three types of endocytosis, the removal of portions of the plasma membrane to form vesicles is balanced with the addition of plasma membrane from vesicle fusion during exocytosis, so there is no significant loss or gain of the plasma membrane surface area.

1. cellular products such as hormones and neurotransmitters are released by the process of ___.

○ receptor - mediated endocytosis
○ pinocytosis
○ phagocytosis
○ exocytosis

1. phagocytosis and pinocytosis differ in that ___.

○ pinocytosis is more selective than phagocytosis
○ phagocytosis allows for the transport of larger particles than pinocytosis
○ one is a type of exocytosis, and one is a type of endocytosis
○ almost all cells are capable of phagocytosis, while few select cell types are capable of pinocytosis

1. the most specific type of endocytosis is ___.

○ receptor - mediated endocytosis
○ pinocytosis
○ phagocytosis

Explanation:

1. The text states that in exocytosis, cellular products from the endoplasmic reticulum and Golgi apparatus are packaged into vesicles, move to the membrane and fuse with it to release products. Hormones and neurotransmitters are such cellular products released by exocytosis.
2. Phagocytosis is for large - particles (cell eating) while pinocytosis is for ingesting extracellular fluid and its solutes (cell drinking), so phagocytosis allows for transport of larger particles.
3. Receptor - mediated endocytosis involves cell surface receptors specifically binding an external substance for ingestion, making it the most specific type of endocytosis.

Answer:

1. D. exocytosis
2. B. phagocytosis allows for the transport of larger particles than pinocytosis
3. A. receptor - mediated endocytosis