Leaflets of Mimosa pudica (common names: sensitive plant, touch-me-not) have a remarkable ability to close up in response to being touched or physically moved. How fast can the leaflets close? How does this occur? And more importantly, what benefit could this unusual response provide to the plant?Mimosa leaflets also close on their own at dusk and reopen at dawn (this cycle develops as a circadian rhythm). What receptor molecule mentioned in this chapter is likely involved in regulating this process?

Leaflets of Mimosa pudica (common names: sensitive plant, touch-me-not) have a remarkable ability to close up in response to being touched or physically moved. How fast can the leaflets close? How does this occur? And more importantly, what benefit could this unusual response provide to the plant?The mechanism of leaflet closure is similar to what happens during the shrinking of guard cells and closing of stomata (see Figure 37.22). When in the open position, special cells on the upper surface of Mimosa leaflets are filled with water and are under pressure. Explain how osmosis and flow of ions into and out of these special cells may be involved in leaflet closure and reopening.

Leaflets of Mimosa pudica (common names: sensitive plant, touch-me-not) have a remarkable ability to close up in response to being touched or physically moved. How fast can the leaflets close? How does this occur? And more importantly, what benefit could this unusual response provide to the plant?If just the leaflets located toward the end of a leaf are touched, the adjacent leaflets close in fairly rapid succession until all leaflets on a leaf close up. Explain how electrical signaling may be involved in this response.

Leaflets of Mimosa pudica (common names: sensitive plant, touch-me-not) have a remarkable ability to close up in response to being touched or physically moved. How fast can the leaflets close? How does this occur? And more importantly, what benefit could this unusual response provide to the plant?Researchers have hypothesized that rapid leaf movements in Mimosa serve as a defense mechanism (e.g., closing leaflets may deter plant-eating insects). Propose an experiment to test this hypothesis.

If apples are to be stored for long periods, it is best to keep them in a place with good air circulation. Explain why.

Write a short paragraph explaining why a houseplant becomes bushier if you pinch off its terminal buds.

What is growth that results in curvatures of whole plant organs toward or away from stimuli called?

The immediate, direct effect of auxin in cell elongation, according to the acid growth hypothesis, is to __________.

In addition to interacting with auxin in the control of apical dominance, newly discovered plant hormones help to establish mycorrhizal associations by attracting mycorrhizal fungi to the plant roots. What are these hormones called?