9 Mar 2017
School
Department
Course
1. Flowers
a. photoperiod
i.
ii. Plants are dictated by how long it is in the DARK, not the amount of time
in the day
b. Exam deals with only short day plants
c. Phytochrome
i.
ii. In short day plants, phytochrome FAR RED inhibits the growths of flowers
in short day plants
iii. Takes 20 seconds for phytochrome red to turn into phytochrome far red
1. This happens during the day time
iv. To get rid of this inhibitor, it has to be in the dark
1. This takes a long time
2. Decays the far red during the night
3. In tobacco it takes 16 hours of darkness to get rid of far red
v. The amount of time varies for each plant
1. If you flash a beam of light during the middle of the night for just
20-30 seconds
a. Any far red that was decayed becomes far red agains
b. Causes no growth of flowers