A Bio question

Test Preparation SAT Subject Test Preparation
1

<p>In Barron's Practice test 1 #84 it has a beaker with 5% saline and a plant cell dropped into it. </p>

<p>The choices:</p>

<p>A. the solution is hypotonic to the cell, and the cell will swll and burst
B. the solution is hypotonic to the cell, and the cell will become turgid
c. the solution is hypertonic to the cell, but nothing will happen to the cell
d. the solution is hypertonic to the cell and the cell will shrink
e. the solution is hypertonic to the cell, and the cell will swell</p>

<p>I thought the answer would be B since if the solution is 5% saline, it will be 95% water. Since there must be more water outside, the water will go into the cell and burst it, but since it's a plant cell, it will become turgid.</p>

<p>Barron's answer say it's D & I didn't understand its explanation...
D. The cell is in a 5% solution that is hypertonic to any cell. Water will flow out of the cell into the surrounding solution, and the cell will shrink.</p>

<p>Explain... anyone? :(</p>

2

<p>Hypertonic refers to a solution of higher concentration of solute (dissolved particles). I think of hyper as in “high” “over” etc. So since the solution has a higher salt content, water will flow out of the cell, and solute will flow in to reach equilibrium. Water flowing out=shrinkage</p>

<p>I always got “hypertonic” and “hypotonic” confused until I thought of it in terms of dissolved solute. Hope that helps :)</p>

3

<p>if theres a 5% saline, thats more of a concentration than water. water flows towards the hypertonic area. the saline will be more concentrated than water, which means the water will flow out of the plant cell, causing the plant cell to shrink</p>

4

<p>water follows solute =] always.</p>

5

<p>well, hypertonic means that there is higher concentration of the solute inside the cell than outside the cell. So that means thta there is more water inside the cel 100% vs the 95% in outisde. So by diffusion it goes from hight to low and thecell shrinks</p>