Question

Which statement best explains how methylene blue stain works in the yeast viability test?

Group of answer choices

Dead cells turn blue because nondividing cells can't pump out the stain and retain it within.

Dead cells will turn blue because they are unable to metabolize the stain.

Dead cells turn blue because they stop diving and stop absorbing the stain.

Living cells will turn blue because they are actively metabolizing the methylene blue stain.

Answer 1

The correct option is b.

Dead cells turn blue in a yeast viability test using methylene blue stain because they cannot metabolize and are thus unable to expel the stain, differentiating them from live, unstained cells.

Step-by-step explanation:

The statement that best explains how methylene blue stain works in the yeast viability test is that dead cells will turn blue because they are unable to metabolize the stain.

Methylene blue is a type of viability or vital stain which works on the principle that live cells possess the ability to reduce the stain and hence do not retain it, remaining colorless, while dead cells have lost this metabolic ability and thus get stained blue as they cannot expel the absorbed stain.

This technique helps distinguish between living and deceased cells in a culture, making it valuable for determining cell viability.