What is the oxidation state of iron in haemoglobin?

(1)  Fe^-

(2)  Fe²⁺

(3)  Fe³⁺

(4)  Fe⁴⁺

Mature RBCs lose their ability for

(1) DNA replication

(2) Anaerobic respiration

(3) Aerobic respiration and DNA replication

(4) Aerobic respiration, DNA replication and RNA synthesizing machinery

Haemoglobin is

(1) an oxygen carrier in human blood

(2) a protein used as food supplement

(3) an oxygen scavenger in root nodules

(4) a plant protein with high lysine content

The transport of respiratory gases is taken care by which blood component?

(1) RBC

(2) WBC

(3) Platelets

(4) Fibrinogen

Hemoglobin in healthy individual:

(1) 12–20 g/10 mL of blood

(2) 12–14 g/100 mL of blood

(3) 12–30 g/10 mL of blood

(4) 12–14 g/10 mL of blood