Exam 39: Plant Signals and Behavior

Which of the following colors of visible light induces phototrophic curvature in coleoptiles most effectively?

Which of the following environmental factors can be sensed by plants? I. gravity II. pathogens III. wind IV. light

If a farmer wanted less tightly packed clusters of grapes, he would most likely spray the immature bunches with which of the following hormones?

Which of the following is an adaptation that allows woody species to survive freezing temperatures?

A gardener in Canada wants to surprise his mother on her birthday and make her favorite hibiscus bush flower in May instead of at the end of June. The bush is growing in the greenhouse. Which of the following treatments is most likely to make the hibiscus bush flower early?

Charles and Francis Darwin discovered that ________.

A particular type of virus carries a gene for salicylate hydroxylase, an enzyme that breaks down salicylic acid. Which of the following responses is most likely?

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 of the following best explains the reduction in fitness in the mutant plant?

You want to alter the shape of a growing plant, causing it to bend by applying auxin to one side of the stem. Application at which of the following positions, A, B, C, or D would produce the greatest bending?

Which of the following plant responses requires integration of auxin, cytokinin, and strigolactone?

Corn seeds were germinated on two petri dishes of agar containing a colored pH indicator. The dishes were placed on edge with the seedling oriented either vertically (A) or horizontally (B). After 24-hours growth, the plates appeared as in C and D. Dark areas in D indicate lower pH. Which of the following statements is supported using the data?

Which of the following mechanisms is most directly responsible for controlling circadian rhythms in plants?

Seed packets give a recommended planting depth for the enclosed seeds. Which of the following is the most likely reason some seeds are to be covered with only a thin layer of soil after planting?

Mammalian eyes sense light because the photoreceptor cells have molecules called opsins that change structure when exposed to light. Which of the following plant molecules is most analogous to mammalian opsins in their light-sensing ability?

Which of the following is involved in the rapid leaf movements resulting from a response to touch (thigmotropism)?

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 treatments has the best chance of creating iris blooms in winter?

Which of the following must occur for a plant to initiate chemical responses to herbivory, before it is directly affected by herbivores?

Most scientists agree that climate change 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?

Which of the following detects light during de-etiolation (greening) of a tomato plant?

Use the figure to answer the following question. Suppose you laid a seedling on its side so that the root was parallel to the ground as shown in the figure. Several hours after the change in position, in which labeled position(s), A, B, or C in the figure, are statoliths most likely to be located?