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WorksheetsNitrogen fixation - N and S assimilation & anaplerotic reaction
Total questions: 17
Worksheet time: 17mins
Nitrogen fixation is an
anaerobic process
aerobic process
microaerophilic process
aeroleterant process
N2 fixation that takes place under high temperature and pressure, in the presence of Fe or Ru as catalyst is
Biological N fixation
Industrial N fixation
both
atmospheric N fixation
The nitrogen fixation organisms are….A….. and are commonly called as….B……
A- Prokaryotes or eukaryotes and B - diazotrophs
A- Prokaryotes and B - piezotrophs
A- Prokaryotes and B - diazotrophs
A-eukaryotes and B-piezotrophs
An example for associative symbiotic nitrogen fixer
Rhizobium
Azotobacter
Clostridium
Azospirillum
The amount of biological nitrogen fixed annually is
50-100 terra g N / year
100-140 terra g N / year
100-200 terra g N / year
<50 terra g N / year
Which of the following process could mediate atmospheric nitrogen fixation
cosmic radiation
meteorite trails
lightning
all the above
Nif genes are those that codes for
nitrogenase enzyme
nitrate reductase
nitric oxide reductase
Urease
identify the CORRECT statements related to nitrogenase enzyme
(i) highly substrate specific
(ii) Reqs Fe & Mo for its activity
(iii) commonly it functions under low and high temperatures
(iv) reqs. 14-16 ATP for their activity
both (i) and (ii)
(i) only
(ii) & (iv)
(iii) & (iv)
A cation that is much essential for the activity of the nitrogenase enzyme is
Ca2+
Mg2+
Na
K
An example for symbiotic nitrogen fixer
Rhizobium
Azotobacter
Clostridium
Azospirillum
Enzyme(s) commonly invovled in N assimilation is
glutamate dehydrogenase
glutamine synthase
glutamate synthase
All the three
nitrogenase
An example for anaerobic nitrogen fixer
Rhizobium
Azotobacter
Clostridium
Azospirillum
Enzyme diamide and enzyme hydrazine refers to
enzyme-substrate intermediate forms resulted during N2 fixation
forms of enzymes involved in N2 fixation
Alternative nitrogenase forms
changes in shape of enzyme after bonding of N2
Acetylene, cyanide and carbon monoxide are
subrates for nitrogenase
poison the functioning of nitrogenase
coenzyme or co-factors of the nitrogenase
can be substrates or poisons depending upon the conditions
Identify the CORRECT statements related to nitrogenase enzyme
(i) it is a primitive enzyme like rhodonase
(ii) it can also use proton and electron as substrate to produce H2
(iii) it is coded by nif genes
(iv) expression of nif genes in the plant by rDNA technology is a currently available technology
All the statements are correct
(i), (ii) & (iii)
(i) and (ii)
(iv) alone
The main protein of the nitrogenase are coded by the genes
nif AL
nif HDK
nif F
nif XNE
Nitrogenase is subjected to regulation controls by
O2
NH3
NO3
Nif L gene products
all the above
