Final answer:
Osmolarity is the concentration of solutes in a solution. Iso-, hypo-, and hyper-osmotic are terms used to compare osmolarity inside and outside of a cell. In a hypotonic situation, water enters the cell to equalize solute concentration.
Step-by-step explanation:
Osmolarity refers to the concentration of solutes in a solution. In biology, it is used to describe the concentration of solutes inside and outside of a cell. The terms iso-, hypo-, and hyper-osmotic are used to compare the osmolarity of the extracellular fluid to the osmolarity inside the cell. An iso-osmotic solution has the same osmolarity as the cell, a hypo-osmotic solution has a lower osmolarity, and a hyper-osmotic solution has a higher osmolarity. In a hypotonic situation, where the extracellular fluid is hypo-osmotic compared to the cell, water enters the cell to equalize the solute concentration.
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