The question asks to identify which of the given options is NOT a reducing sugar. To answer this, we need to understand the definition of a reducing sugar and examine the structures of the given carbohydrates.
B) Sucrose — Sucrose is a disaccharide formed by an \(\alpha\)-1,2-\(\beta\)-glycosidic bond between glucose and fructose. Both anomeric carbons are involved in the glycosidic linkage, leaving no free anomeric carbon to open up and form an aldehyde or ketone group. Hence, sucrose is a non-reducing sugar.
The question asks about the products formed when lactose is hydrolyzed by lactase. This is a fundamental concept in biochemistry, specifically carbohydrate metabolism. Lactose is a disaccharide, and its hydrolysis breaks it down into its constituent monosaccharides.
A) Glucose + Galactose — This is correct because lactose is a disaccharide formed by the condensation of one molecule of glucose and one molecule of galactose. Hydrolysis, catalyzed by lactase, reverses this process, yielding these two monosaccharides.
The question asks for the molecular formula of glucose. Glucose is a monosaccharide, a simple sugar, and its chemical composition is well-established in chemistry.
Correct Option: D) C₆H₁₂O₆ is the correct molecular formula for glucose, a hexose sugar.
The question asks about the monomeric unit that makes up chitin, a structural polysaccharide found in insect exoskeletons. To answer this, one needs to recall the basic composition of chitin.
A) N-acetylglucosamine units — Chitin is a linear homopolysaccharide composed of repeating units of N-acetyl-\(\beta\)-D-glucosamine, linked by \(\beta\)-1,4-glycosidic bonds. This makes it structurally similar to cellulose but with an N-acetylamino group at C-2 instead of a hydroxyl group.
The question asks about the basic building blocks (monomers) of proteins. Understanding the fundamental composition of macromolecules is crucial in biology and biochemistry.
A) Amino acids — Proteins are indeed polymers of amino acids. A long chain of amino acids linked by peptide bonds forms a polypeptide, which then folds into a specific three-dimensional structure to become a functional protein.
This question tests fundamental knowledge about the types of chemical bonds found in biological macromolecules. Specifically, it asks about the bond that links amino acids to form proteins. Recall the basic building blocks of proteins and how they are joined.
Correct Option: C) Peptide bond — A peptide bond is the amide linkage formed between the carboxyl group of one amino acid and the amino group of another amino acid, with the elimination of a water molecule. This is the defining bond that forms the primary structure of proteins.