Final answer:
Blood is formed through the process of hematopoiesis in the red bone marrow. Hematopoietic stem cells differentiate into myeloid and lymphoid lineages to produce different types of blood cells.
Step-by-step explanation:
Blood is formed through the process of hematopoiesis, which is the production of red blood cells, white blood cells, and platelets in the red bone marrow.
This process occurs in a tissue called red marrow, found inside some bones.
Hematopoietic stem cells differentiate into myeloid and lymphoid lineages, giving rise to the different types of blood cells.
The production of blood cells occurs through the proliferation and differentiation of stem cells in the marrow.