Question

Cells formed in bone marrows include:
A. RBC only
B. RBC and leukocytes
C. Leukocytes only
D. Lymphocytes only

Answer 1

Hint: Bone marrow is found at the centre of the bone. It is composed of many blood vessels. The bone marrow contains the blood stem cells. It is the primary centre for haematopoiesis.

Complete Answer:
To solve this question, we must know about the blood cells and their formation.
Types of blood cells:
1. RBC or erythrocytes- These cells contain haemoglobin which is the carrier of oxygen. It is produced in the red bone marrows.
2. WBC or Leukocytes- The white blood cells or the leukocytes are produced in the bone marrow. Its main function is to protect our body from the foreign particles. It is found in the blood and lymphatic system.
3. Thrombocytes or platelets- These cells are responsible for blood clotting. The 60-70% of platelets are produced in the bone marrow.
4. Lymphocytes- It is a type of WBC which includes B cells and T-cells. They are produced in the bone marrows.

The correct answer is, (B). 'Cells formed in bone marrows include RBC and leukocytes.'

Additional Information: In bone marrow disease the stem cells production is either increased or decreased. Leukemia is associated with abnormal bone marrow in which it makes abnormal white blood cells. In case of aplastic anaemia the bone marrow does not produce RBC.

Note: The bone marrows are important in producing the blood cells. The Red bone marrow produces blood cells whereas the yellow bone marrow is associated with the storage of fat.