Model of cry1 interactions with COP1/SPA1 in the regulation of photomorphogenesis, what will happen in the dark as well as in the light in wild type condition of cryptochrome?

a) In the dark, COP1/SPA1 acts to degrade transcription factors such as HY5, which is required for photomorphogenesis

b) In the dark, cry1 is activated by phosphorylation and forms a complex with COP1 and SPA1 via the C-terminal domain, preventing them from degrading protein HY5

c) In the light, COP1/SPA1 acts to degrade transcription factors such as HY5, which is required for photomorphogenesis

d) In the light, cry1 is activated directly by blue light and indirectly by blue light induced phosphorylation and forms a complex with COP1 and SPA1 via the C-terminal domain, preventing them from degrading protein HY5

e) In light as well as in dark both case cryptochrome perfom same function such as forming a complex with COP1/ SPA1 thereby promoting an increase in HY5 protein levels and transcription

Which of the following combinations from the above statements of cryptochrome is incorrect?

#Question id: 11602

#Unit 6. System Physiology – Plant

The concentration of gibberellins in plants is very low usually 1–10 parts per billion for the _____A_________ in _______B________ and up to 1 part per million of total gibberellins in ______C________.

#Question id: 11603

#Unit 6. System Physiology – Plant

Several important role promotes GA in the plant except____

#Question id: 11604

#Unit 6. System Physiology – Plant

What will be the effect of exogenous gibberellin in plant?

a) extreme stem elongation in dwarf plants

b) Increases  in stem thickness

c) decrease in leaf size

d) decreases in stem thickness

e) Increases in leaf size

f) pale green color of the leaves

#Question id: 11605

#Unit 6. System Physiology – Plant

Major uses of gibberellins applied as a spray or dip, are to manage several processes except,

#Question id: 11606

#Unit 6. System Physiology – Plant

What will be the effect light in GA biosynthesis?

a) Light basically activates the GA 3β-hydroxylase which adds a hydroxyl group (OH) to carbon 3 of GA20 and convert GA20 to GA1

b) light-induced increase in the transcription of the gene for GA3ox, which converts GA20 to GA1

c) light-induced increase in the transcription of the gene for GA2ox, which converts GA20 to GA29

d) light-induced decreases the transcription of the gene for GA3ox, which converts GA20 to GA1

#Question id: 11607

#Unit 6. System Physiology – Plant

How the active gibberellin GA1 is inactived by?

a)  By hydroxylation remove GA20 from the biosynthetic pathway by converting it to GA1

b) conversion to GA8 by a hydroxylation on carbon 2

c) By hydroxylation remove GA20 from the biosynthetic pathway by converting it to GA29