Exam 39: Plant Responses to Internal and External Signals

Auxins in plants are known to affect which of the following processes? I.gravitropism of shoots II.maintenance of seed dormancy III.phototropism of shoots IV.inhibition of lateral buds V.apical dominance

Generally, each hormone has multiple functions in plants depending on ________. I.site of action II.its concentration III.developmental stage IV.age

A plant scientist was hired by a greenhouse operator to devise a way to force iris plants to bloom in the short days of winter. Iris normally blooms as a long-day (short-night) plant. Which of the following has the best chance of creating iris blooms in winter?

Shoots that grow vertically toward the sun can be characterized as ________.

The signaling molecule for flowering might be released earlier than usual in a long-day plant exposed to flashes of

If you were shipping green bananas to a supermarket thousands of miles away, which of the following chemicals would you want to eliminate from the plants' environment?

The rapid leaf movements resulting from a response to touch (thigmotropism) primarily involve ________.

What are the primary sites of ethylene production in high concentrations in plants?

Plant hormones produce their effects by ________. I.altering the expression of genes II.modifying the permeability of the plasma membrane III.modifying the structure of the nuclear envelope membrane

What are the primary sites of auxin (IAA) production in plants?

Who might be interested in using cytokinins?

In extremely cold regions, woody species may survive freezing temperatures by ________.

An individual plant was discovered that could not grow towards light. After some research, it was determined that the reason was a defective gene that did not allow for the level of cell elongation necessary for a phototropic response. This mutation greatly reduces the fitness of the individual plant. Which reason best describes the reason for the loss of fitness?

Many plants flower in response to day-length cues. Which of the following statements best summarizes this phenomenon?

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.

A particular species of virus carries a gene for salicylate hydroxylase, an enzyme that breaks down salicylic acid. Will this virus be more or less virulent to plants than other viruses?

An eccentric millionaire botanist has offered a $25,000 scholarship to anyone who can successfully get a plant to grow through a vertical maze in complete darkness. The maze is not in a box; the maze is simply drawn on the wall, and the contestants must get their plant to grow in a pattern that matches the path through the maze. You need the money and feel confident that you can accomplish this task. Which of the following techniques will help you succeed?

Suppose a plant had a photosynthetic pigment that absorbed far-red wavelengths of light. In which of the following environments could that plant thrive?

Most scientists agree that global warming is underway; thus, it is important to know how plants respond to heat stress. Which of the following would be a useful line of inquiry to try and improve plant response and survival to heat stress?

Apical dominance in plants is under the control of ________.