Question

Formation of red blood is called _________?
A. Haemocytosis
B. Haemolysis
C. Haemopoiesis
D. Haemocytolysis

Answer 1

Hint: Blood is composed of different cells such as red blood cells, white blood cells, and platelets. The process of formation of these cells is initiated in the bone marrow. The bone marrow contains a haematopoietic stem cell (HSC) that undergoes differentiation to form the different blood components.
Another word for formation is ‘poiesis’.

Complete answer:
Haemopoiesis, also known as haematopoiesis is the formation of red blood. It is the process by which the different components of blood, namely RBCs, WBCs, and platelets are formed.
Haematopoiesis originates in the bone marrow. The Haematopoietic Stem Cell is a multipotent cell that is capable of differentiating into different cell lines, i.e. myeloid and lymphoid cell lines.

> Myeloid Cell Line
A myeloid progenitor cell is produced after HSC differentiation.
This progenitor cell further differentiates into Megakaryocyte, Erythroblast and Myeloblast.
The megakaryocyte differentiates to form platelets.
Erythroblast differentiates to form erythrocytes (RBCs).
Myeloblasts differentiate to form Monocytes, Neutrophils, Basophils, and Eosinophils.

> Lymphoid Cell Line
A lymphoid progenitor cell is produced after HSC differentiation.
This progenitor further differentiates into T-lymphocyte, B-lymphocyte and Natural Killer cells.

There are certain growth factors that facilitate haematopoiesis:
- Erythropoietin
- Thrombopoietin
- Interleukins
- Colony-stimulating factors
- Negative regulators

Hence, the correct answer is option (C).

Note: Blood is actually a tissue that acts as a transport medium for various components in the body. For example,
- The RBCs bind to oxygen and transport it throughout the body.
- The WBCs are important components of the immune system.
- Platelets help in blood clotting by forming a haemostatic plug at the site of injury.