Question

Which of the following destroys worn-out RBCs?
(a) Liver
(b) Kidney
(c) Spleen
(A) a,b
(B) a,c
(C) b,c
(D) All of the above

Answer 1

Vital organs in the human body in which one organ helps in detoxification which is also the largest gland in the body and other organs helps in immune system functions located below the stomach.

Complete answer:
Erythrocytes or red blood cell’s life span is 120 days. After 120 days in the circulation, they are removed by macrophages which are a type of myeloid phagocytic cells. They are located primarily in the liver, spleen, and bone marrow. The worn-out RBC is destroyed in the spleen and liver.

Additional Information:
- Circular, biconcave, and enucleate RBC are found in mammals.
- The biconcave shape of erythrocytes provides a large area for the exchange of gases.
- Mammalian RBC has a diameter of 7.8 micrometers and 5 million RBC are present per cubic millimeter of blood.
- Mammalian RBC is surrounded by a plasma membrane. Nucleus and other cell organelles are lost in the reticulocyte stage of its development.
- A chromoprotein, hemoglobin is present in the cytoplasm of RBC
- 4 polypeptide chains and 4 heme molecules are present in each hemoglobin molecule.
- They live for 120 days in the circulation and are removed by the liver and spleen
- The protein portion in RBC i.e, globulin breakdown to amino acids and is used by bone marrow for the production of RBC
- Heme portion consists of iron which is stored in the liver and spleen in the form of ferritin.

So, the correct answer is 'a,c’.

Note:
-The RBC that are not undergone phagocytosis, after 120days they break down into alpha and beta chains which are removed by the kidneys from the circulation.
-Vitamin $B_12$ and folic acid are required for the maturation of erythrocytes.