Biomolecules complete

What enzyme deficiency causes lactose intolerance?,

Lactase deficiency.

What is the primary cause of lactose intolerance?,

Reduction of intestinal brush border lactase activity in adults.

How does lactase deficiency affect digestion?,

Undigested lactose ferments in the gut, causing bloating and diarrhea.

Is lactose a reducing sugar?,

Yes, because its anomeric carbon is free and not linked by a glycosidic bond.

What type of bond connects a monosaccharide to a purine base in nucleotides?,

N-glycosidic bond.

What are the major milk allergens?,

Casein, α-lactoglobulin (ALA), and β-lactoglobulin (BLG).

What is the primary structural protein in milk?,

Casein.

Why is milk white?,

Fat globules and casein micelles scatter light, giving milk its opaque white color.

How does milk transform into cheese?,

Through acidification, coagulation of casein proteins, and removal of whey.

What enzyme is primarily responsible for milk coagulation in cheese production?,

Chymosin (rennet).

What is whey protein?,

A mixture of proteins isolated from the liquid portion of milk during cheese production.

Which amino acid in whey protein is the most anabolic?,

Leucine.

What are the primary macronutrients in milk?,

Proteins, lipids, and carbohydrates (lactose).

What type of fats are prominently found in cow milk?,

Medium-chain and long-chain fatty acids.

What are the two essential fatty acids?,

Omega-3 (α-linolenic acid) and Omega-6 (linoleic acid).

What is the primary health benefit of Omega-3 fatty acids?,

They reduce the risk of cardiovascular diseases.

How does trans fat affect human health?,

Increases LDL cholesterol, decreases HDL cholesterol, and raises cardiovascular disease risk.

What is the function of lung surfactant?,

Prevents alveolar collapse by reducing surface tension in the lungs.

Which phospholipid is the major component of lung surfactant?,

Dipalmitoylphosphatidylcholine (DPPC).

At what stage of fetal development does surfactant production reach normal levels?,

Around the 8th month of gestation.

What condition results from surfactant deficiency in premature infants?,

Neonatal respiratory distress syndrome (NRDS).

What are structural lipids in membranes?

,Phospholipids and cholesterol, which provide stability and fluidity.

What is the primary structure of a protein?,

The linear sequence of amino acids connected by peptide bonds.

What stabilizes a protein's secondary structure?,

Hydrogen bonds forming α-helices and β-sheets.

What are the forces stabilizing tertiary protein structure?,

Hydrophobic interactions, hydrogen bonds, ionic bonds, and disulfide bridges.

What is protein denaturation?,

The loss of protein structure due to heat, pH changes, or chemical agents.

What is the main function of casein in milk?,

Acts as a carrier for calcium and phosphate.

What is the primary function of cholesterol in cell membranes?,

Maintains membrane fluidity and stability.

What is the difference between lactose intolerance and cow’s milk allergy?,

Lactose intolerance is an enzyme deficiency, whereas milk allergy is an immune response to milk proteins.

How is excess cholesterol removed from the body?,

Converted to bile acids and excreted in feces.

What is the role of phospholipids in membranes?,

They form the lipid bilayer, providing structural integrity and compartmentalization.

Why are trans fats banned in many countries?,

Why are trans fats banned in many countries?,

What is the major role of branched-chain amino acids (BCAAs)?,

They promote muscle protein synthesis and reduce muscle breakdown.

How do Omega-3 fatty acids influence brain function?,

They support neuronal growth, cognitive function, and reduce inflammation.

What enzyme is responsible for hydrolyzing lactose into glucose and galactose?,

Lactase.

What is the importance of calcium in milk?,

It supports bone development and muscle function.

What is the main component of the extracellular matrix in animal cells?

,Collagen, which provides structural support.

What is the primary source of energy storage in animals?,

Triacylglycerols (fats) stored in adipose tissue.

What are glycoproteins?,

Proteins with attached carbohydrate chains, important for cell recognition and signaling.

What is the significance of disulfide bonds in proteins?,

They stabilize the 3D structure of proteins, especially extracellular proteins.

What are the key components of a nucleotide?,

A nitrogenous base, a sugar (ribose or deoxyribose), and a phosphate group.

What is the function of hemoglobin?,

Transports oxygen in the blood by binding to oxygen in red blood cells.

How does pH affect enzyme activity?,

Extreme pH levels can denature enzymes, altering their activity.

What is the role of insulin in metabolism?,

It lowers blood glucose by promoting glucose uptake and storage as glycogen and fat.

Which amino acids are essential in humans?,

Private TIM HaLL: Phenylalanine, Threonine, Tryptophan, Isoleucine, Methionine, Histidine, Arginine, Leucine, Lysine.

What is the role of rennet in cheese making?,

Rennet contains enzymes that coagulate milk proteins, forming curds.

What is the function of lipase in fat digestion?,

Lipase breaks down triglycerides into glycerol and free fatty acids.

Why is Omega-6 fatty acid important?,

It plays a role in inflammation, blood clotting, and cell membrane structure.