What does Type A blood indicate about the antigens present in the individual's blood?

Type A blood is characterized by the presence of only antigen A on the surface of red blood cells. This specific antigen is a carbohydrate structure that is recognized by the immune system. Individuals with Type A blood can produce antibodies against antigen B, which means they cannot receive blood containing antigen B without risking an immune response. Therefore, the presence of only antigen A in Type A blood is a defining feature, distinguishing it from other blood types that contain different or additional antigens. Understanding this is crucial for blood transfusions, as compatibility between donor and recipient blood types is essential for patient safety.