❤️Blood types are determined by the presence of antigens A and B, with O blood type lacking both antigens.
🔴Erythrocytes, or red blood cells, contain hemoglobin that binds to oxygen for transportation.
🅰️Type A blood has antigen A, while type B blood has antigen B. Type AB blood has both antigens, and type O blood lacks both.
🩸The Rh factor, indicated by + or -, determines the presence or absence of the D antigen and can complicate transfusions and pregnancies.
🌍Blood types exist in different species, with humans having fewer variations compared to animals like dogs.