Question

a solution surrounding a cell is __ if it contains more nonpenetrating solute particles than the interior of the cell; thus water moves __ the cell by osmosis.
a) hypertonic, into
b) hypotonic, out of
c) hypotonic, into
d) hypertonic, out of

question 7 (mandatory) (0.5 points)
if a red blood cell was placed in a hypotonic solution, it will undergo ____.
a) crenation
b) pinocytosis
c) no net change in size
d) hemolysis

Explanation:

First Question (Osmosis and Tonicity)

A hypotonic solution has a lower solute concentration (higher water concentration) than the red blood cell's interior. By osmosis, water moves into the red blood cell. Red blood cells do not have a cell wall, so they will swell as water enters. Eventually, the cell may burst, and this process is called hemolysis. Crenation (A) occurs in a hypertonic solution (water moves out, cell shrinks). Pinocytosis (B) is a type of endocytosis (cell drinking), not related to tonicity - induced volume change. No net change (C) occurs in an isotonic solution, not a hypotonic one.

Answer:

D. hypertonic, out of; C. hypotonic, into (Wait, let's re - evaluate. For the first part: A solution surrounding a cell is hypertonic if it has more non - penetrating solute particles than the cell's interior. In osmosis, water moves from an area of lower solute concentration (higher water potential) to higher solute concentration (lower water potential). So if the surrounding solution is hypertonic (more solute), water moves out of the cell. So the correct option for the first question is D. hypertonic, out of? Wait, no, let's re - check the options:

Option A: hypertonic, into – No, hypertonic outside means water moves out.

Option B: hypotonic, out of – Hypotonic outside has less solute, water moves in.

Option C: hypotonic, into – Hypotonic outside (less solute) so water moves into the cell (from low solute to high solute, i.e., from outside hypotonic to inside higher solute). Wait, I think I messed up. Let's recall: Tonicity is about the relative solute concentration. A hypertonic solution has more solute (less water) than the cell. So water moves out of the cell (from cell to hypertonic solution). A hypotonic solution has less solute (more water) than the cell, so water moves into the cell.

So the first question: "A solution surrounding a cell is __ if it contains more nonpenetrating solute particles than the interior of the cell; thus water moves __ the cell by osmosis."

First blank: hypertonic (since more solute outside). Second blank: out of (since water moves from cell (less solute, more water) to outside (more solute, less water)). So the correct option is D. hypertonic, out of.

Question 7 (Red Blood Cell in Hypotonic Solution)