Biological Nitrogen Fixation

Q.

Which amino acid plays role in nitrogen metabolism?

Q.

How much nitrogen is in the human body?

Q. The nitrate absorbed by the plant is converted into ammonia in the

1. Branches

2. Leaves

3. Roots

4. Stem

Q.

An element playing important role in nitrogen fixation is?

1. zinc

2. molybdenum

3. copper

4. manganese

Q. The biological conversion of ammonium to nitrite and then to nitrate is called .

1. nitrogen fixation
2. nitrification
3. ammonification
4. denitrification

Q. In non leguminous plant, a bacterium that develops root nodules is

1. Azotobacter
2. Thiobacillus
3. Frankia
4. Rhizobium

Q.

Actinorhizal plants means?

Q.

Assertion (A): Higher plants can not utilize nitrogen that is present in the form of $N_2$ in air.

Reason (R): In higher plants, the nitrogenase enzyme is absent.

1. Both A & R are true and R explains A

2. Both A & R are true and R does not explain A

3. Both A & R false

4. A is true and R is False

Q.

Identify the correct equation related to the mechanism of biological nitrogen fixation.

1. N₂+8H⁺+8e^-+16ATP 2NH₃+H₂+16ADP+16Pi

2. N₂+6H⁺+8e^-+12ATP 2NH₄⁺+12ADP+12pi

3. N₂+8H⁺+6e^-+16ATP 2NH₃+H₂+16ADP+16pi

4. N₂+6H⁺+6e^-+12ATP 2NH+12ADP+12pi

Q. Rhizobium has symbiotic relationship with the roots of __

Q.

The process of nitrogen-fixation by bacteria does not take place in the presence of

1. molecular form of hydrogen

2. elemental form of oxygen

3. water

4. elemental form of nitrogen

Q.

Are all eubacteria pathogens?

Q. Plant can assimilate nitrogen in the form of

1. $N_2$
2. ${\mathrm{NO}}_2^{-}$
3. ${\mathrm{NO}}_3^{-}$
4. ${\mathrm{NH}}_3$

Q.

Symbiotic nitrogen fixing bacteria in stem of Sesbania rostrata is:

1. Azorhizobium

2. Sinorhizobium

3. Photorhizobium

4. Bradyrhizobium

Q. Which of the following are correct about type Ⅱ endonucleases?
(a) They require ATP for their activity.
(b) They are bifunctional enzymes having nuclease and methylase activity.
(c) They breaks the sugar-phosphate backbone at the recognition site.
(d) They are naturally found in prokaryotes.

Choose the correct option:

1. a and b
2. a and d
   
3. b and c
4. c and d

Q.

Who conducts denitrification?

Q. Chemosynthetic bacteria are those bacteria

1. Which carry out photosynthesis
2. Which synthesize food without light
3. Which carry out photosynthesis in absence of light
4. Which are unable to carry out chemical process

Q.

Match the column I and column II.
$\begin{array}{cc}ColumnI& ColumnII\\ A.Nitrobacter& 1.Free-livingaerobic{N}_{2}fixer\\ B.Clostridium& 2.Convertsammoniaintonitrite\\ C.Nitrosococcus& 3.Changesnitritetonitrate\\ D.Azotobacter& 4.Free-livinganaerobic{N}_{2}fixer\end{array}$

1. $\begin{array}{ccccc}& A& B& C& D\\ & 1& 2& 3& 4\end{array}$

2. $\begin{array}{ccccc}& A& B& C& D\\ & 4& 2& 1& 3\end{array}$

3. $\begin{array}{ccccc}& A& B& C& D\\ & 3& 4& 2& 1\end{array}$

4. Codes
   $\begin{array}{ccccc}& A& B& C& D\\ & 2& 4& 3& 1\end{array}$

Q. For its activity, nitrogenase requires

1. high input of energy
2. manganese
3. super oxygen radicals
4. light

Q. Which among these elements is required for the action of enzyme nitrogenase an enzyme needed for biological nitrogen fixation?

1. $Zn$
2. $Mg$
3. $Mo$
4. $Ca$

Q.

The enzyme nitrogenase is a

1. Fe-Protein

2. Mo-Protein

3. Mo-Fe Protein

4. Pure Protein

Q. Which of the following organism causes nodule formation?

1. Azotobacter
2. Anabaena
3. Rhizobium
4. Nostoc

Q. Give the correct terminologies for the following processes : conversion of organic nitrogen into ammonia, $N_2$ gas to ammonia and ammonia into nitrates respectively.

1. Nitrogen fixation, denitrification, ammonification
2. Ammonification, nitrogen fixation, nitrification
3. Nitrification, ammonification, nitrogen fixation
4. Nitrogen fixation, nitrification, ammonification

Q. Some blue green algae can be used as biofertilizer as they are

1. Photosynthetic
2. Surrounded by mucilage
3. Growing every where
4. Capable of fixing nitrogen

Q.

The process of nitrogen-fixation by bacteria does not take place in the presence of

1. molecular form of hydrogen

2. the elemental form of oxygen

3. water

4. elemental form of nitrogen

Q. Assertion :Ammonia should be eliminated from the body as rapidly as it is formed
Reason: Ammonia is insoluble in water.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Both Assertion and Reason are incorrect

Q. Give the correct terminologies for the following processes : conversion of organic nitrogen into ammonia, $N_2$ gas to ammonia and ammonia into nitrates respectively.

1. Nitrogen fixation, denitrification, ammonification
2. Ammonification, nitrogen fixation, nitrification
3. Nitrification, ammonification, nitrogen fixation
4. Nitrogen fixation, nitrification, ammonification

Q. These bacteria grow anaerobically on cellulosic material, produce large amount of methane along with $C{O}_2$ and $H_2$ and are collectively called as methanogens. Examples of such bacteria are:

1. Methanobacterium
2. Methanococcus
3. Mathanobrevibacter
4. All of these

Q. Enzyme required for the following reaction is $N\stackrel{\sim }{=}N\to N{H}_3$

1. Nitrite reductase

2. Amino synthetase

3. Nitrogenase

4. Nitrate reductase

Q. Reaction carried out by $N_2$ fixing microbes include
$2N{H}_3+3O_2\to 2N{O}_2^{-}+2H^{+}+2H_{2}O$ (i)
$2N{O}_2^{-}+O_2\to 2N{O}_3^{-}$ (ii)
Which of the following statements about these equations is not true?

1. Step (ii) is carried out by Nitrobacter
2. Both step (i) and (ii) can be called nitrification.
3. Bacteria carrying out these steps are usually photoautotrophs.
4. Step (i) is carried out by Nitrosomonas or Nitrosococcus