👉 Red blood cells are flat disks made mainly of protein called hemoglobin, which carries oxygen from lungs to tissues. White blood cells act like soldiers, identifying and attacking foreign invaders such as bacteria or viruses.
👉 Red blood cells are flat disks made mainly of protein called hemoglobin, which carries oxygen from lungs to tissues. White blood cells act like soldiers, identifying and attacking foreign invaders such as bacteria or viruses.
