Question

A solution is called hypertonic when:

• A. Osmolarity of the solution is equal to that of cells cytosol \
• B. Osmolarity is lower than the cytosol \
• C. Osmolarity is higher than that of cytosol \
• D. It allows movement of solvent across the semipermeable membrane

Hint:

Hyper = High solute concentration. Water always leaves the cell to dilute the "hyper" environment, causing the cell to shrink.

Answer 1

The Correct Option is C

Step 1: Concept Toxicity describes how an extracellular solution can change the volume of a cell by altering water movement via osmosis.

Step 2: Meaning Prefix meanings: Hyper- means greater or above, Iso- means equal, and Hypo- means under or less. Osmolarity measures total solute concentration per liter of solution.

Step 3: Analysis * If osmolarity equals the cytosol, the solution is isotonic. * If osmolarity is lower than the cytosol, the solution is hypotonic. * If osmolarity is higher than that of the cytosol, it contains a higher concentration of non-penetrating solutes, making it hypertonic. This causes water to exit the cell.

Step 4: Conclusion Thus, higher solute concentration (osmolarity) outside the cell relative to the cytosol defines a hypertonic solution. Final Answer: (C)