Question

1. red bone marrow only differs from yellow bone marrow because of a difference in the amount of which substance?

the amount of cytokine
the amount of fat
the amount of antibody
the amount of antigen

Explanation:

Red bone marrow is rich in hematopoietic cells and has less fat, while yellow bone marrow has a higher amount of fat cells (adipocytes). Cytokines are signaling molecules, antibodies are part of the immune response (produced by plasma cells, not mainly differentiating marrow types), and antigens are substances that can trigger an immune response. The key difference between red and yellow bone marrow is the fat content.

Answer:

the amount of fat