The biological role of Cytochrome P-450 is

1. Nitrogen fixation

2. Oxidation of RH to ROH

3. Amide hydrolysis

4. Oxidation of amino acid.

Myoglobin is a

1. Catalyst for epoxidation reaction

2. Component in a photosynthetic system

3. Nitrogen fixation enzyme

4. Di-oxygen binding metalloprotein

The metal that is not prevalent in the biological system is

1. Platinum

2. Manganese

3. Cobalt

4. Nickel

Hemerythrin belongs to the group of

1. Non-heme iron protein

2. Binuclear copper protein

3. Heme-iron protein

4. None of these. 

Which of the following metalloproteins does not have iron in the active site?

1. Hemoglobin

2. Hemerythrin

3. Hemocyanin

4. Cytochrome c

Which of the following is a heme iron protein?

1. Rubredoxin

2. Transferrin

3. Hemerythrin

4. Cytochrome c

The reduction of nitrogen to ammonia, carried out by the enzyme nitrogenase needs

1. 2e^- 

2. 4e^- 

3. 6e^- 

4. 8e^- 

Iron-sulphur clusters in biological systems are involved in

1. proton transfer

2. atom transfer

3. group-transfer

4. e^- transfer

The extent of $\mathrm{\pi }$ electron conjugation in macrocyclic rings (i) heme, (ii) coenzyme B₁₂ and (iii) chlorophyl follows the order

1. (i)>(iii)>(ii)

2. (i)>(ii)>(iii)

3. (iii)>(i)>(ii)

4. (ii)$\approx$(i)>(iii)

Oxidized form of enzyme catalase (structure A); prepared by the reaction of [Fe(P)]⁺ (P=porphyrin) with H₂O₂ has a green colour because of

1. Oxidation state of iron changed from Fe^III to Fe^IV.

2. Porphyrin ring is oxidized by one electron.

3. $\mathrm{\pi }-\mathrm{\pi }*$ transition appears in the visible region

4. Fe^IV is coordinated with anionic tyrosinate ligand in axial position.