Question

in what important way does receptor - mediated endocytosis differ from phagocytosis?
it transports only small amounts of fluid.
it does not involve the pinching off of membrane.
it brings in only a specifically targeted substance.
it brings substances into the cell, while phagocytosis removes substances.
none of these answer choices are correct.

question 14
many viruses enter host cells through receptor - mediated endocytosis. what is an advantage of this entry strategy?
the virus directly enters the cytoplasm of the cell.
the virus is protected from recognition by white blood cells.
the virus only enters its target host cell type.
the virus can directly inject its genome into the cells nucleus.
the virus can enter many different cell types.

question 15
imagine a cell can perform exocytosis, but only minimal endocytosis. what would happen to the cell?
the cell would secrete all its intracellular proteins.
the plasma membrane would increase in size over time.
the cell would stop expressing integral receptor proteins in its plasma membrane.
the cell would lyse.
the er and golgi would break apart.

Explanation:

1. Question 13: Receptor - mediated endocytosis is highly specific as it uses receptor proteins to bind and bring in specific substances. Phagocytosis is more general, engulfing large particles or microorganisms. So the key difference is that receptor - mediated endocytosis brings in only a specifically targeted substance.
2. Question 14: Receptor - mediated endocytosis is specific. Viruses use this method to enter only their target host cell types, which is an advantage as it allows for targeted infection.
3. Question 15: Exocytosis involves the cell secreting materials and adding membrane components to the plasma membrane. Endocytosis takes in materials and recycles membrane. If a cell has a lot of exocytosis and little endocytosis, the plasma membrane will increase in size over time as more membrane is added than removed.

Answer:

1. Question 13: It brings in only a specifically targeted substance.
2. Question 14: The virus only enters its target host cell type.
3. Question 15: The plasma membrane would increase in size over time.