Kailey flashcards

Biochemistry Notes 2/27/26, and 3/6/26.

What does Hemoglobin A1C measure?

It measures long-term blood glucose control over 6–12 weeks.

What does Hemoglobin A1C indicate about proteins?

It provides information on the glycation of proteins.

Why is glycation important in diabetes?

People with diabetes often have elevated protein glycation, leading to AGEs (advanced glycation end products).

What is a glycosidic bond?

A bond that links monosaccharides to alcohols or amines.

What is an O-glycosidic bond?

A bond between an anomeric carbon atom and an oxygen atom of an alcohol.

What is an N-glycosidic bond?

A bond between an anomeric carbon and an amine group.

Why is phosphorylation of sugars important?

It adds a charge to carbohydrates, preventing them from crossing the cell membrane and facilitating metabolism.

What are oligosaccharides?

Carbohydrates made of 2 or more monosaccharides linked by glycosidic bonds.

What is maltose composed of?

Two glucose molecules.

Why are monosaccharides linked?

They are linked to form complex polysaccharides.

What are the three main disaccharides?

Sucrose, lactose, and maltose.

What is sucrose made of and how is it broken down?

Glucose + fructose > cleaved by sucrase in the intestine.

What is lactose and how is it broken down?

A milk disaccharide > cleaved by lactase in the intestine.

What is maltose and how is it broken down?

A degradation product of large oligosaccharides. A disaccharide of two glucose units, and hydrolyzed by maltase.

What is glycogen?

The storage form of glucose in animals.

What type of bonds are found in glycogen?

α-1,4 glycosidic bonds with α-1,6 branches every ~12 glucose units.

What is starch?

The storage form of glucose in plants.

Waht glucose polymers are in starch (plants)?

Amylose, and amylopectin.

What is amylose?

A linear glucose polymer with α-1,4 glycosidic bonds.

What is amylopectin?

A branched glucose polymer with an α-1,4 backbone and α-1,6 branches (~every 24 residues).

What is cellulose?

A structural polysaccharide in plants made of glucose.

What type of bonds are in cellulose?

Homopolymer linked by β-1,4 glycosidic bonds.

Why is cellulose structurally strong?

Parallel chains form fibrils that provide plant support.

How do α-linkages differ from β-linkages structurally?

α-linkages form bent structures (storage), while β-linkages form rigid, straight structures (support).

What are unsaturated fats?

Fats that contain double bonds and are not fully saturated with hydrogen.

What are saturated fats?

Fats that are fully hydrogenated (saturated with hydrogen), typically solid at room temperature and common in butter.

What is hydrogenation?

The process of adding hydrogen (H₂) to fats, often converting unsaturated fats into more saturated forms.

What are trans fats?

Fats produced during hydrogenation that are most common and harmful to heart health.

What is the effect of trans fats on cholesterol?

They increase LDL (bad cholesterol).

What role do organic acids play in membranes?

They can adjust membrane fluidity based on temperature.

What is the structure of unsaturated fatty acids?

They have more double bonds, which increases fluidity.

Why are trans fats similar to saturated fats?

Their bonds are straight up and down, allowing tight packing like saturated fats.

What is the structure of cis fats?

They are “bendy” due to double bonds, preventing tight packing.

What is the effect of cis fats?

They cause less aggregation and are generally better for membranes.

Why are trans fats harmful?

They increase the risk of heart disease.

How do trans fats affect arteries?

They pack tightly around blood vessels, decreasing artery diameter and clogging blood flow.

What are the three common membrane lipids?

Phospholipids, glycolipids, and sphingolipids.

What are phospholipids?

Membrane lipids made of fatty acids, glycerol, phosphate, and an alcohol group.

What are the components of phospholipids?

1–2 fatty acids, glycerol backbone, phosphate group, and an alcohol.

What are ester bonds?

Bonds that attach fatty acids to the glycerol backbone in phospholipids.

What makes membranes amphipathic?

Molecules that contain a hydrophilic head and hydrophobic tail.

What is the structure of a phospholipid?

A hydrophilic head and hydrophobic tails.

What is the hydrophilic head?

The phosphate-containing region that interacts with water.

What is the hydrophobic tail?

The fatty acid chains that repel water.

What determines phospholipid variation?

The type of alcohol group attached.

What is phosphatidylserine?

A type of phospholipid distinguished by its alcohol group.

What is phosphatidylethanolamine?

A type of phospholipid distinguished by its alcohol group.

What is phosphatidylcholine?

The most common phospholipid type.

What is phosphatidylinositol?

A phospholipid involved in membrane structure and signaling.

How are glycerol backbone bonds formed?

Through dehydration reactions with fatty acids.

What is the ester linkage formula?

R–O–C=O.

What are glycolipids?

Membrane lipids with sugar chains attached.

What is the function of sugars in glycolipids?

They are involved in cell recognition.

What roles do glycolipids play?

They help in cell adhesion and protection.

What are the two types of glycolipids?

Glycerolipids and sphingolipids.

What are glycerolipids?

Glycolipids based on a glycerol backbone.

What are sphingolipids?

Glycolipids based on a sphingosine backbone.

What is in the glyco-/phospho- head group?

Sugar + alcohol + phosphate.

What some main functions of glycolipids?

They are important for cell-to-cell communication, cell recognition and immune response.