A group of single-cell organisms collected from the ocean was brought into the lab for examination. The lab assistant was concerned that the water had become full of toxic waste products and so added clean water to the culture. All of the organisms died, and when she looked at them under the microscope, all she could see were bits and pieces of them scattered throughout the water. What likely happened?
A) She added water that was hypotonic to the culture of organisms, and they ruptured.
B) She added seawater to which she had added too much salt, and they ruptured.
C) She added water isotonic to the organisms, causing too much water to move in and out of the organisms, and they ruptured.
D) She added too little salt to the seawater she added, and the organisms all lost too much water and shriveled up.

Question

Quizplus · Accepted Answer

When the lab assistant added clean water that was hypotonic (had lower concentration of solutes) to the culture of organisms, water moved inside the organisms causing them to swell and eventually rupture. This leads to the scattering of bits and pieces of the organisms throughout the water seen under the microscope.

A Group of Single-Cell Organisms Collected from the Ocean Was