Exam 39: Plant Responses to Internal and External Signals

A researcher found a beautiful plant while traveling in Alaska and collected its seeds.When she came back to Florida,she soaked some seeds in pure water and some in water with a hormone.When she put the seeds in soil to grow,only the seeds that had been soaked with the hormone germinated.The hormone most likely was

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 might make the hibiscus bush flower early?

This experiment suggests that the unknown amount of gibberellin in the experimental plant (B)is approximately

In nature,poinsettias bloom in early March.Research has shown that the flowering process is triggered three months before blooming occurs.In order to make poinsettias bloom in December,florists change the length of the light-dark cycle in September.Given the information and clues above,which of the following is a correct statement about poinsettias?

-What conclusion can you draw from the result in the question above.

Unlike animal hormones,plant hormones are mainly

The synthesis of which of the following hormones would be a logical first choice in an attempt to produce normal growth in mutant dwarf plants?

The major function of the medicinal compounds in plants is to

The biological clock controlling circadian rhythms must ultimately

In cases where plants exhibit generalized defence responses in organs distant from the infection site,this is termed

Upon exposure to blue light,plants not only begin to grow toward the light,but move their chloroplasts to the sunny side of each cell.The adaptive advantage of moving chloroplasts to the sunny side of each cell

What does a short-day plant require in order to flower?

If protein synthesis was blocked in etiolated cells,what would be necessary for the "greening" of these cells?

Which of the following would only be activated or upregulated after a plant has already been infected by a pathogen?

You are part of a desert plant research team trying to discover crops that will be productive in arid climates.You discover a plant that produces a hormone under water-deficit conditions that triggers a suite of drought responses.Most likely the hormone is

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

Plants growing in a partially dark environment will grow toward light in a response called phototropism.Which of the following statements is true regarding phototropism?

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

Plant cells begin synthesizing large quantities of heat-shock proteins

Plants are affected by an array of pathogens.Which of the following is a likely plant defence/response against disease?