question_answer

Cytochrome is a:

A)  Mg pyrole ring

B)  Fe porphyrin ring

C)  nucleotide     

D)  alloy of nichrome

Correct Answer: B

Solution :

 Cytochromes are iron-containing heme prosthatic groups. They are most important electron carriers of the respiratory chain which are related with each other by the presence of a bound heme group whose iron^atom changes from ferric \[(F{{e}^{+3}})\] state to ferrous \[(F{{e}^{+2}})\] state when it accepts an electron. The heme group of cytochromes consists of a porphyrin ring holding an iron atom with its four nitrogens.