Question

A solute passively diffuses through a transport protein out of the cell. What is the tonicity of the fluid inside the cell?

1) hypertonic
2) hypotonic
3) isotonic
4) none of these
5) more than one of these

Answer 1

When a solute passively diffuses out of the cell due to a higher internal solute concentration, the fluid inside the cell is hypertonic in relation to the outside.

Step-by-step explanation:

If a solute passively diffuses through a transport protein out of the cell, this implies that there is a higher concentration of the solute inside the cell compared to outside. The fluid inside the cell would therefore be hypertonic to the fluid outside the cell. Tonicity is a measure of the osmotic pressure gradient of two solutions separated by a semipermeable membrane. In a hypertonic situation, the inside of the cell has a higher concentration of solutes than the external environment, causing water to move out of the cell in an attempt to equalize the solute concentration on both sides of the membrane. In this case, the tonicity of the fluid inside the cell is option 1) hypertonic.