Final answer:
Antigens on the surface of red blood cells determine blood types and are not associated with oxygen transport. They develop before birth and are key in blood type differentiation.c) Antigens
Step-by-step explanation:
Proteins on the surface of red blood cells, which develop before birth and are distinct from the blood's oxygen-transporting proteins, are known as antigens.
These surface antigens can be proteins, carbohydrates, glycoproteins (proteins attached to chains of sugars), or glycolipids (lipids attached to chains of sugars) and play a crucial role in determining blood type. In the ABO blood group system, the well-known antigens are glycolipids, specifically antigen A and antigen B. Those with blood type A have antigen A, those with blood type B have antigen B, individuals with type AB carry both, and those with type O have neither. Blood types are thus distinguished based on the presence or absence of these different antigens found on the surface of red blood cells.