Question

Which of the following is an example of the transport of insulin and cholesterol into animal cells?

exocytosis

endocytosis

passive transport

none of the above

Answer 1

The transport of insulin and cholesterol into animal cells is an example of the process endocytosis.
Endocytosis is a process of ingestion in which the plasma membrane folds inward to bring substances into the cell. Exocytosis on the other hand is a proces in which the contents of the cell (water-soluble molecules such as proteins) are secreted into the extracellular environment.
So, the process in our case in an endocytosis because it is a process in which the cell takes in items that are outside the cell,not a process (exocytosis) in which the cell is releasing molecules to be taken in by another cell.

exocytosis content is released from the cells.

Answer 2

Cholesterol and insulin are taken inside the cell by through a receptor mediated ENDOCYTOSIS process. These macromolecules bind to the complementray protein of the receptor, and then are engulfed inside the cell. If this process stops, cholesterol starts accumulating in the blood vessels, increasing the chances of a heart attack. Similarly, insulin if not taken up, may lead to increased levels of glucose in the blood.