Pset8plantquestions

Part 2 of 3 photoreceptors and light question 1 of 9

Info iconThis preview shows pages 4–7. Sign up to view the full content.

View Full Document Right Arrow Icon
Part 2 of 3 - Photoreceptors and Light Question 1 of 9 4.0 Points Young leaves that emerge from the coleoptile of a developing seedling are all rolled up, like a rolled-up newspaper. Unrolling of the leaves involves physiological changes within the leaves including cell expansion. After being exposed to light, they quickly unroll into the flat conformation that is typical of a grass leaf blade. How would you determine if leaf unrolling is a phytochrome mediated response? A. treat with far-red light (l ~ 730 nm) to see if phytochromes are produced B. treat with far-red light (l ~ 730 nm) to see if unrolling is stimulated C. treat with near-red light (l ~ 660 nm)to see if unrolling is inhibited
Background image of page 4

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
5/29/13 8:53 PM 2013 Plant Biology Lectures 8-10 Problem Set 8 Page 5 of 11 https://coursework.stanford.edu/portal/tool/1c2f43e9-1653-4e97-98f7-93a4fbb2cb09/jsf/delivery/beginTakingAssessment D. treat with near-red light (l ~ 660 nm)to see if unrolling is stimulated E. none of the above Reset Selection Mark for Review What's This? Question 2 of 9 4.0 Points How might you determine if leaf unrolling described in the previous question is mediated by gibberellin ( one of the plant hormones ) in a phytochrome dependent manner? i,e., how can you show that phytochrome activation changes the production, release, or activity of giberellins which in turn causes leaf unrolling. Pick experiment(s) that would help support this model A. treat the seedling with gibberellin in the dark and observe response B. Generate mutant seedlings lacking in gibberellin, treat with red light and observe C. treat the seedling with white light and test for changes in gibberellin concentration, release, and/or activity D. treat the seedling with red light and test for changes in gibberellin concentration, release, and/or activity E. All of the above Reset Selection Mark for Review What's This? Question 3 of 9 4.0 Points In a short-day (long-night) plant with a critical day length of 15 hours, flowering would be induced by _______ hours of light alternating with _______. A. 12; 12 hours of darkness B. 16; 8 hours of darkness C. 16; 8 hours of darkness D. 14; 8 hours of darkness E. 8; 8 hours of darkness F. 15; 9 hours of darkness, interrupted by one short burst of white light Reset Selection Mark for Review What's This? Question 4 of 9 4.0 Points Which of the following treatments of seeds that require light for germination would promote germination? A. Treatment with blue light B. Treatment with red light C. Treatment with far-red light
Background image of page 5
5/29/13 8:53 PM 2013 Plant Biology Lectures 8-10 Problem Set 8 Page 6 of 11 https://coursework.stanford.edu/portal/tool/1c2f43e9-1653-4e97-98f7-93a4fbb2cb09/jsf/delivery/beginTakingAssessment D. Treatment with red light then far-red light E. Treatment with blue light then far-red light Reset Selection Mark for Review What's This?
Background image of page 6

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 7
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

Page4 / 11

Part 2 of 3 Photoreceptors and Light Question 1 of 9 40...

This preview shows document pages 4 - 7. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online