Nitrate reductase is an important enzyme for nitrate assimilation. Given below some regulation of nitrate reductase activity through phosphorylation and dephosphorylation.

a) Light, and other environmental factors stimulate a protein phosphatase that dephosphorylates a key serine residue in the hinge 1 region of nitrate reductase and thereby activates the enzyme

b) In Dark, and Mg2+ stimulate a protein kinase that phosphorylates the same serine residues, which then interact with a 14-3-3 inhibitor protein, and thereby inactivate nitrate reductase

c) In Light, and Mg2+ stimulate a protein kinase that phosphorylates the serine residues, and thereby activate nitrate reductase

d) In Dark, and other environmental factors stimulate a protein phosphatase that dephosphorylates a key serine residue in the hinge 1 region of nitrate reductase and thereby inactivates the enzyme

Which of the following statements about regulation of nitrate reductase is correct?

TLS Online TPP Program

#Question id: 28078

#Unit 6. System Physiology – Plant

Chlorophyll functions on the phenomenon of absorption of light and shows excitation of electron

(a) Chlorophyll absorbs blue or red light 

(b) blue light absorption resulting in a higher excited state 

(c) red light absorption resulting in a higher excited state 

(d) From IInd exited state returning ground state heat will be observed from blue and fluorescence from red light

Which of the following is incorrect

TLS Online TPP Program

#Question id: 28079

#Unit 6. System Physiology – Plant

In molecules, two types of excited states can exist singlet and triplet  

(a) The singlet state is relatively long‐lived than triplet and have parallel spin

(b) The singlet state is relatively short‐lived than triplet and have antiparallel spin

(c) The triplet state is relatively long‐lived than singlet and have two parallel spin

(d) The triplet state is relatively long‐lived than singlet and have two anti-parallel spin

Which of the following is correct 

TLS Online TPP Program

#Question id: 28080

#Unit 6. System Physiology – Plant

Excitation of chlorophyll RC has various ways to dissipate energy, which of the following is not a way to dissipate energy 

a. Heat

b. Fluorescence

b. energy transfer

d. Photochemistry via charge separation

Which of the following is correct 

TLS Online TPP Program

#Question id: 28081

#Unit 6. System Physiology – Plant

In the phenomenon of transfer of electron in photosystem have various time order

(a) Splitting of H2O – 1ms

(b) Transfer of electron from Mn – Z – in Microseconds 

(c) Transfer of electron from Z – P680 – in Nanosecond 

(d) 1st photochemistry - picoseconds

Which of the following is correct

TLS Online TPP Program

#Question id: 28082

#Unit 6. System Physiology – Plant

Which of the following functions as a water‐plastoquinone oxidoreductase

TLS Online TPP Program

#Question id: 28083

#Unit 6. System Physiology – Plant

What will be quantum yield when 1O2 as a photochemical product is formed per 10 Quanta absorbed