Exam 39: Plant Responses to Internal and External Signals

A plant mutant that shows normal gravitropic bending but does not store starch in its plastids would require a reevaluation of the role of ________ in gravitropism.

What is the probable role of salicylic acid in the defense responses of plants?

Which of the following best explains both the growth of a vine up the trunk of a tree as well as the directional growth of a houseplant toward a window?

Which of the following plant hormones would most likely be found in high concentrations in a mature, slightly overripe fruit?

All of the following may function in signal transduction in plants except

If a farmer wanted more loosely packed clusters of grapes, he would most likely spray the immature bunches with

Auxin enhances cell elongation in all of the these ways except

Which of the following best describes positive gravitropism exhibited by plant roots?

According to the acid growth hypothesis, auxin works by

Unlike animal hormones, plant hormones are mainly

Which type of mutant would be most likely to produce a bushier phenotype?

Plants that have their flowering inhibited by being exposed to bright lights at night are

After some time, the tip of a plant that has been forced into a horizontal position grows upward. This phenomenon is related to

A botanist discovers a plant that lacks the ability to form starch grains in root cells, yet the roots still grow downward. This evidence refutes the long-standing hypothesis that

Why do coleoptiles grow toward light?

Which of the following plant hormones would be found in very low amounts in a mature, water-stressed tomato plant?

Which of the following hormones would be most useful in promoting the rooting of plant cuttings?

A plant seedling bends toward sunlight because

The ripening of fruit and the dropping of leaves and fruit are principally controlled by

Which of the following would be the most effective way to prevent herbivory in a non-woody plant?