TLS Online TPP Program

#Question id: 10348


During ammonium assimilation, requires two enzymes converting ammonium to amino acids. Each of which is Glutamine synthetase (GS), given below some statements about GS ;

a) GS transfers the amide group of glutamine to 2-oxoglutarate, yielding two molecules of glutamate

b) it requires a divalent cation such as Mg2+, Mn2+, or Co2+ as a cofactor

c) Plants contain two classes of GS, one in the cytosol and the other in root plastids or shoot chloroplasts

d) The cytosolic forms are expressed in germinating seeds or in the vascular bundles of roots and shoots and produce glutamate for intercellular nitrogen transport

e) The GS in root plastids generates amide nitrogen for local consumption; the GS in shoot chloroplasts reassimilates photorespiratory NH4+

f) Light and carbohydrate levels alter the expression of the cytosolic forms of the enzyme, but they have little effect on the plastid forms.

Which of the following statements is correct?

#Unit 6. System Physiology – Plant
  1. a, d and f
  2. c, d and e
  3. a, b and f
  4. b, c and e