Exam 39: Plant Responses to Internal and External Signals

The following questions refer to the description below. Plants are not able to move away from predators, so they have evolved chemical methods to protect themselves. Biologists have observed that caterpillars munching on a leaf can be attacked by certain species of wasps. These wasps lay their eggs inside the caterpillar's body, and when the eggs hatch, the larvae feed on its host from the inside. -How do wasps find plants with caterpillars? You design an experiment in which one group of plants is torn/shredded by human fingers, another group of plants has leaves cut off with plant shears, a third group of plants has leaves stapled, and the fourth group of plants has leaves eaten by caterpillars. After several days of observation, only the plant with caterpillars has attracted wasps. The most likely conclusion is that

A botanist exposed two groups of the same plant species to two photoperiods: one with 14 hours of light and 10 hours of dark and the other with 10 hours of light and 14 hours of dark. Under the first set of conditions, the plants flowered, but they failed to flower under the second set of conditions. Which of the following conclusions would be consistent with these results?

Plant hormones can have different effects at different concentrations. This explains how

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

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

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?

How does indoleacetic acid affect fruit development?

Why might animal hormones function differently than plant hormones?

Which of the following plant growth responses is primarily due to the action of auxins?

In order for a plant to initiate chemical responses to herbivory,

Vines in tropical rain forests must grow toward large trees before being able to grow toward the sun. To reach a large tree, the most useful kind of growth movement for a tropical vine presumably would be the opposite of

Most scientists agree that global warming is under way; 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 hormones would be most useful in promoting the rooting of plant cuttings?

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

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

If a short-day plant has a critical night length of 15 hours, then which of the following 24-hour cycles will prevent flowering?

Experiments on the positive phototropic response of plants indicate that

In legumes, it has been shown that "sleep" (nastic)movements are correlated with

Which of the following field treatments would be most likely to result in a wheat or corn field with most of the plants of uniform height?

The plant hormone involved in aging and ripening of fruit is