37. Plant Sensation and Response

What is phototropism?

Why is phototropism important for plants?

How would a houseplant typically respond to sunlight that comes from only one direction?

Which pigment is primarily responsible for detecting the photoperiod in plants?

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

The face of a sunflower turns to follow the sun as it moves across the sky. This is an example of:

You are interested in determining what part of a plant senses the light, which leads to phototropism. A good first experiment would be to __________.

A certain short-day plant flowers when days are less than 12 hours long. Which of the following treatments will result in flowering?

What are circadian rhythms?

Some seeds require light for germination. This process is controlled by the phytochrome system. Which of the following germination treatments would inhibit germination of such seeds?

An Alaskan trapper worried about being attacked by grizzly bears left the lights on in his cabin all the time. Plants just outside the cabin flowered a month early. Which of the following best explains this?

A conformational change in a substance called phytochrome __________.