The pair in which both the species have iron is:

Options

A. nitrogenase, cytochromes
B. carboxypeptidase, haemoglobin
C. haemocyanin, nitrogenase
D. haemoglobin, cytochromes

Answer

D

Explanation

Cytochromes are conjusgated proteins consisting of an aproprotein and a prosthetic group `(` haeme `)`. The haeme consists of a porphyrin with a certral iron atom.
The name haemoglobin is the concentration of haeme and globin, reflecting the fact that each subunit of haemoblobin is a globular protein with an iron atom, and this is responsible for the binding of oxygen. The most common types of haemoglobin contains four such subunits, each with one heme group.