True or False: Blood cells are formed within the bones.

Blood cells are indeed formed within the bones, primarily in the bone marrow, which is a spongy tissue found in the center of certain bones. This process of blood cell formation is known as hematopoiesis. In humans, this occurs in various bones throughout the body, including both the axial skeleton (such as the spine, ribs, and skull) and the appendicular skeleton (which includes the limbs and pelvic bones). The bone marrow produces red blood cells, white blood cells, and platelets, all crucial for oxygen transport, immune response, and blood clotting, respectively. Thus, stating that blood cells are formed within the bones is accurate, reaffirming the correctness of the answer.