Question

a student measures the mass of each of six potato cores and places one core in each of the unknown solutions. after a period of time, the student removes the potato cores and measures the mass of each one. the results are shown in the table.

solution	potato core mass
2	decrease
3	no change
4	no change
5	decrease
6	increase

which statement best describes a conclusion the student can make about the results?

a solution 1 is hypertonic because water flowed out of the cells of the potato.
b solution 6 is hypertonic because water flowed out of the cells of the potato.
c solutions 2 and 5 are hypotonic because water entered the cells of the potatoes.
d solutions 3 and 4 are isotonic because water flowed equally in and out of the cells of the potatoes.

Explanation:

In osmosis, in an isotonic solution, there is no net movement of water, resulting in no change in potato - core mass. Solutions 3 and 4 show no change in potato - core mass, indicating they are isotonic as water flows equally in and out of the cells. A hypertonic solution would cause water to flow out of the potato cells (decrease in mass), and a hypotonic solution would cause water to flow into the potato cells (increase in mass).

Answer:

D. Solutions 3 and 4 are isotonic because water flowed equally in and out of the cells of the potatoes.