Two yeast cells, one of type a and the other type α, are in proximity to each other. The a yeast cell has a mutation in the gene for the α factor receptor protein such that the receptor does not translocate to the surface of the a cell. If both cells secrete their respective a and α factors, which of the following outcomes is most likely to occur?
A)The a and α cells will grow toward each other.
B)The a cell will grow towards the α cell.
C)The α cell will grow toward the a cell.
D)The a and α cells will not grow toward each other at all.

Question

Quizplus · Accepted Answer

The α cell will grow toward the a cell because it secretes α factor which will diffuse towards the a cell. The a cell is unable to respond to the α factor due to its mutation, but it can still secrete its own a factor. The a factor will not attract the α cell, so the α cell will grow towards the a cell.

Two Yeast Cells, One of Type a and the Other