Cycle 2 - Carbohydrates and Blood Group Antigens

What sugar acts as the primary energy source in your blood?

Glucose. It is the body’s go-to fuel during cellular respiration.

Which monosaccharide is found in fruit and is the sweetest natural sugar?

Fructose. It's common in fruit juices and sweetened drinks.

Which sugar combines with glucose to form milk sugar (lactose)?

Galactose. This is also the sugar people can’t digest well in lactose intolerance.

Which monosaccharide forms part of DNA?

Deoxyribose. It’s the “D” in DNA (Deoxyribonucleic Acid).

What makes some sugars act as blood antigens?

Their position and type in oligosaccharide chains on red blood cell (RBC) membranes. Specific sugars like galactose or N-acetylgalactosamine help label blood type A, B, AB, or O.

What sugar acts as the primary energy source in your blood?

Glucose. It is the body’s go-to fuel during cellular respiration.

Which monosaccharide is found in fruit and is the sweetest natural sugar?

Fructose. It's common in fruit juices and sweetened drinks.

Which sugar combines with glucose to form milk sugar (lactose)?

Galactose. This is also the sugar people can’t digest well in lactose intolerance.

Which monosaccharide forms part of DNA?

Deoxyribose. It’s the “D” in DNA (Deoxyribonucleic Acid).

What makes some sugars act as blood antigens?

Their position and type in oligosaccharide chains on red blood cell (RBC) membranes. Specific sugars like galactose or N-acetylgalactosamine help label blood type A, B, AB, or O.

Why is N-acetylglucosamine (GlcNAc) important in your immune system?

It helps cells recognize and communicate with each other. GlcNAc is found in glycoproteins which are part of cell signaling and immune identification, helping your immune system distinguish between self and foreign cells.

What could happen if blood with a different sugar chain is transfused into your body?

Agglutination may occur, leading to a dangerous immune reaction. The antibodies in the recipient’s plasma recognize the unfamiliar sugar and trigger clumping of red blood cells

What makes type O blood different at the molecular level?

It has only the base H antigen; no added terminal sugar. The O gene is non-functional and doesn’t add a sugar to the H antigen. This makes it a universal donor but reactive if not matched in Rh factor

How do glycosyltransferase enzymes determine blood type?

By adding specific sugars to red blood cell surfaces. A adds N-acetylgalactosamine, B adds galactose, and O adds none

Why are oligosaccharides compared to cellular name tags?

Because they identify your cells as “self” to the immune system. These sugar chains act as markers that prevent your immune system from attacking your own red blood cells