Question 1

Blood is produced in the red bone marrow in infants after birth.

In infants after birth, blood production predominantly occurs in the red bone marrow, which takes over from the liver and spleen that were responsible for hematopoiesis during fetal development.

A) Heart chamber

The heart chamber is responsible for pumping blood throughout the body but does not play a role in blood production. Therefore, this option is incorrect as it does not relate to the hematopoietic function required for blood formation.

B) Red bone marrow

Red bone marrow is the primary site of blood cell production in infants after birth. It is rich in hematopoietic stem cells, which differentiate into various blood cells, making this option the correct answer.

C) Liver

While the liver is involved in blood production during fetal development, its role diminishes significantly after birth. By this stage, the red bone marrow has taken over the primary function of hematopoiesis, rendering this option incorrect for postnatal blood production.

D) Spleen

The spleen plays a minor role in blood cell production after birth. Although it can assist in the production of blood cells under certain circumstances, it is not the main site for hematopoiesis in infants, making this option incorrect.

Conclusion

The red bone marrow is definitively the correct answer as it is the primary site for blood production in infants after birth, while the heart, liver, and spleen do not serve this function in the same capacity postnatally. Other options fail to reflect the shift in hematopoiesis that occurs after birth, emphasizing the central role of red bone marrow in producing blood.