Question

1. all of the following statements about red blood cells are true except

a. hemocytoblasts give rise to all types of blood cells.
b. red blood cells transport oxygen to body cells and transport some carbon dioxide from body cells.
c. mature red blood cells contain a nucleus.
d. red blood cells contain hemoglobin, which binds to oxygen.

Explanation:

To solve this, we analyze each option:

• Option a: Hemocytoblasts (stem cells) do give rise to all blood cells, so this is true.
• Option b: Red blood cells (RBCs) carry O₂ to cells and some CO₂ away, which is correct.
• Option c: Mature RBCs in mammals lack a nucleus (they lose it during maturation to maximize hemoglobin and oxygen - carrying capacity), so this statement is false.
• Option d: RBCs have hemoglobin that binds to O₂, which is true.

Answer:

c. Mature red blood cells contain a nucleus.