The role of N-terminus and the C-terminus region of the cryptochrome is given below;

a) N-terminal region is involved in the dimerization of cryptochrome and conformational changes

b) C terminus of cryptochrome forms a complex with SPA1 and COP1 that prevents them from acting, thereby preventing the degradation of HY5

c) N-terminal region of cryptochrome forms a complex with SPA1 and COP1 that prevents them from acting, thereby preventing the degradation of HY5

d) Arabidopsis plants overexpressing only the C-terminal region of cryptochrome (CCT) which resemble light-grown seedlings when grown in darkness

Which of the following combinations from the above statements is correct?

#Question id: 10465

#Unit 6. System Physiology – Plant

This feature is an adaptive, as the redistribution of chloroplasts within the cells modulates light absorption and prevents photodamage, diagram shows of chloroplast distribution patterns in Arabidopsis palisade cells in response to different light intensities;

m) A-low light, B-high light, C-darkness

n) A-high light, B-darkness, C-low light

Based on the above light intensities, each shows different chloroplasts position such as,

i) chloroplasts avoid sunlight by migrating to the side walls of palisade cells

ii) chloroplasts move to the bottom of the cell, although the physiological function of this position is unclear

iii) chloroplasts optimize light absorption by accumulating at the upper and lower sides of palisade cells

Which of the following correct combinations shows light intensities and chloroplast movements?

#Question id: 10466

#Unit 6. System Physiology – Plant

In Arabidopsis, phot1 mutants have a normal avoidance response and a poor accumulation response, phot2 mutants lack the avoidance response but retain a fairly normal accumulation response, while phot1/phot2 double mutant lack both the avoidance and accumulation responses. These results indicate that,

#Question id: 10467

#Unit 6. System Physiology – Plant

The COP1-SPA complex acts as a positive regulator as well as acts as negative regulator  by shown in statements;

a) Act as negative regulator−that targets transcription factors for degradation during phytochrome and cryptochrome responses

b) Acts as a positive regulator−that targets transcription factors for degradation during phytochrome and cryptochrome responses

c) Acts as a negative regulator− during UV-B signaling by interacting with the C-terminal region of UVR8 in the nucleus UVR8- COP1-SPA complex then activates the major transcription factor HY5, which controls the expression of many of the genes induced by UV-B

d) Acts as a positive regulator during UV-B signaling by interacting with the C-terminal region of UVR8 in the nucleus UVR8- COP1-SPA complex then activates the major transcription factor HY5, which controls the expression of many of the genes induced by UV-B

Whichof the following combination from avbove statements of UVR8 is true?

#Question id: 10468

#Unit 6. System Physiology – Plant

Why are stomata required in leaf surface?

#Question id: 10469

#Unit 6. System Physiology – Plant

When aquatic plants are kept in terrestrial habitat; what adaptations do these plants develop themselves?

#Question id: 10470

#Unit 6. System Physiology – Plant

when the environmental stimuli associated with high CO2 demand inside the leaf are transduced into