Refer to the figure below showing a signal reception pathway. A mutant plant with an inactive form of the repressor protein (for auxin or gibberellin) is compared to a typical plant.Predict the results of this experiment.
A) The mutant plant is a dwarf because it never transcribes growth promoting genes.
B) The mutant plant transcribes growth promoting genes even in the absence of the relevant hormone.
C) The mutant plant grows more branches than the control plant.
D) The mutant plant does not respond to blue light signals.
E) The mutant plant does not respond to red light signals.

Question

Refer to the figure below showing a signal reception pathway.  A mutant plant with an inactive form of the repressor protein (for auxin or gibberellin) is compared to a typical plant.Predict the results of this experiment.
A) The mutant plant is a dwarf because it never transcribes growth promoting genes. 
B) The mutant plant transcribes growth promoting genes even in the absence of the relevant hormone. 
C) The mutant plant grows more branches than the control plant. 
D) The mutant plant does not respond to blue light signals. 
E) The mutant plant does not respond to red light signals.

Quizplus · Accepted Answer

The repressor protein usually inhibits the transcription of growth-promoting genes in the absence of the relevant hormone. In the mutant plant with an inactive form of the repressor protein, the transcription of these genes is not inhibited even in the absence of the relevant hormone, leading to increased growth and development.

Refer to the Figure Below Showing a Signal Reception Pathway