what cell structure is largely responsible for controlling the entry and exit of substances into or out of the cell?

plasma membrane

Explanation:

The plasma membrane is also known as the cell membrane. It is the boundary between the internal components of a cell and its external surroundings. It controls the entry and exit of substances into or out of the cell and thus, facilitates the exchange of substances between the cells and their external environment.

relationships play a major role in a human's emotional and mental wellbeing. healthy relationships with the people around you are even linked to a smaller production of cortisol, a stress hormone.