Question

Hemoglobin is a
a. Protein
b. Liquid
c. Nucleic acid
d. Carbohydrate

Answer 1

Hint: Hemoglobin is abbreviated as Hb, where it is consists of two parts named heme and globulin and found in the red blood cells, and it is useful to carry the oxygen from the lungs to the body parts and helps for aerobic respiration.

Complete answer:
- Hemoglobin is made up of two parts, namely heme which is an iron complex, and the protein by name globin.
- When it comes to the structure of hemoglobin, it is a quaternary structure.
- It consists of 2 types of proteins, where each protein is again two in number.
- They are alpha and beta chains, where each of them is two in number.
- Each alpha chain in turn consists of 141 amino acids, they are linked up to each other by covalent bonds.
- Each alpha chain is made up of 146 amino acids, where they all are linked to each other by the covalent bonds.
- So the two alpha chains and two beta chains are arranged in tetrahedral form.
- So these complete structures of alpha and beta chains together form the heme complex.
- Where it carries the oxygen molecule, if one subunit gets attached with the oxygen, the structure of the remaining subunits change and make the easy attachment of oxygen to heme and this is called an allosteric effect of heme.
- Globin is the protein part of the heme, which consists of the heme Porphyrin ring, which enables the oxygen affinity more, so it maintains the oxygen transport and all physiologic functions of hemoglobin.

Hence, the correct answer is option (A).

Note: Hemoglobin has an affinity to combine with oxygen and form the Oxyhaemoglobin, where it is formed in the lungs as the partial pressure of oxygen is more in the lungs, when this hemoglobin moves to body parts, here the oxygen is released to body parts and attach to the carbon dioxide as its affinity is more.