Question: what is the main structural difference between monocytes and lymphocytes?
Answer: Monocytes are large, spherical cells that make up 2 to 8% of circulating WBCs. Monocytes can enter peripheral tissues to become tissue macrophages which can engulf large particles and pathogens. Lymphocytes , slightly larger than RBCs, make up 20 to 30% of circulating WBCs. They migrate in and out of the blood.