Final answer:
Glycoproteins are proteins with carbohydrate molecules attached that aid in cell recognition. They contribute to the formation of the glycocalyx, a coating around the cell membrane that allows for cell interactions and recognition. Glycoproteins also play a crucial role in blood grouping.
Step-by-step explanation:
Some integral membrane proteins are glycoproteins. A glycoprotein is a protein that has carbohydrate molecules attached, which extend into the extracellular matrix. The attached carbohydrate tags on glycoproteins aid in cell recognition. The carbohydrates that extend from membrane proteins and even from some membrane lipids collectively form the glycocalyx. The glycocalyx can have various roles, such as allowing cells to bind to each other, containing receptors for hormones, and having enzymes to break down nutrients. The glycocalyces found in a person's body are products of that person's genetic makeup and give each individual's cells an identity. The primary way that the immune defense cells know not to attack the person's own body cells is through the identity provided by the glycocalyces. Additionally, glycoproteins play a crucial role in blood grouping, where the presence or absence of glycoprotein antigens on red blood cell membranes determines the blood type.