Carbohydrates and Carbohydrate Metabolism Study Notes

Carbohydrates and Carbohydrate Metabolism

Monosaccharides

• Definition: Monosaccharides are the simplest form of carbohydrates, consisting of single sugar units.
• General Formula: The general formula of monosaccharides is:
  • Options:
    (A) $CH<em>2O</em>n$
    (B) $C<em>{2n}H</em>{2}O<em>n$ (C) $CH</em>2O<em>{2n}$ (D) $CH</em>2O_{2n}$

Polysaccharides

• Definition: Polysaccharides are long chains of monosaccharide units linked together.
• General Formula: The general formula of polysaccharides is represented as:
  • Options:
    (A) $(C<em>6H</em>{10}O<em>5)$ (B) $(C</em>6H<em>{12}O</em>5)$
    (C) $(C<em>6H</em>{10})$

Types of Sugars

• Aldose Sugar: A sugar that contains an aldehyde group.

  • Examples:
    (A) Glycerose
    (B) Ribulose
    (C) Erythrulose
    (D) Dihydroxyacetone

• Triose Sugar: A sugar that contains three carbon atoms.

  • Examples:
    (A) Glycerose
    (B) Ribose
    (C) Erythrose
    (D) Fructose

• Pentose Sugar: A sugar that contains five carbon atoms.

  • Examples:
    (A) Dihydroxyacetone
    (B) Ribulose
    (C) Erythrose
    (D) Glucose

Specific Pentose Sugars

• Pentose Sugar in Heart Muscle: The major pentose sugar present mainly in heart muscle is:
  • Options:
    (A) Lyxose
    (B) Ribose
    (C) Arabinose
    (D) Xylose

Characteristics of Polysaccharides

• Classification: Polysaccharides are classified as:
  • (A) Polymers
  • (B) Acids
  • (C) Proteins
  • (D) Oils

Isomerism in Glucose

• Number of Isomers of Glucose: The number of isomers of glucose is:

  • Options:
    (A) 2
    (B) 4
    (C) 8
    (D) 16

• Types of Isomers: Sugars which differ from one another only in configuration around a single carbon atom are termed:

  • (A) Epimers
  • (B) Anomers
  • (C) Optical isomers
  • (D) Stereoisomers

• Isomers of Glucose: Isomers differing as a result of variations in configuration of the -OH and -H on carbon atoms 2, 3, and 4 of glucose are known as:

  • (A) Epimers
  • (B) Anomers
  • (C) Optical isomers
  • (D) Stereoisomers

• Most Important Epimer: The most important epimer of glucose is:

  • Options:
    (A) Galactose
    (B) Fructose
    (C) Arabinose
    (D) Xylose

Anomers

• Definition: α-D-glucose and β-D-glucose are examples of:

  • (A) Stereoisomers
  • (B) Epimers
  • (C) Anomers
  • (D) Keto-aldo pairs

• Mutarotation: The reaction represented by α-D-glucose + 112°→+ 52.5°←+ 19° β-D-glucose corresponds to:

  • (A) Optical isomerism
  • (B) Mutarotation
  • (C) Epimerization
  • (D) D and L isomerism

Stereoisomers

• Definition: Compounds having the same structural formula but differing in spatial configuration are known as:

  • (A) Stereoisomers
  • (B) Anomers
  • (C) Optical isomers
  • (D) Epimers

• Structural Orientation: In glucose, the orientation of the -H and -OH groups around the carbon atom 5 adjacent to the terminal primary alcohol carbon determines:

  • (A) D or L series
  • (B) Dextro or levorotatory
  • (C) α and β anomers
  • (D) Epimers

Blood Group Carbohydrates

• Carbohydrate of Blood Group Substances: The carbohydrate present in blood group substances is:
  • Options:
    (A) Sucrose
    (B) Fucose
    (C) Arabinose
    (D) Maltose

Erythromycin Composition

• Composition of Erythromycin: Erythromycin contains:
  • (A) Dimethyl amino sugar
  • (B) Trimethyl amino sugar
  • (C) Sterol and sugar
  • (D) Glycerol and sugar

Sugar Alcohols

• Definition: A sugar alcohol is characterized by:
  • Examples:
    (A) Mannitol
    (B) Trehalose
    (C) Xylulose
    (D) Glucose + Galactose
    (E) Glucose + Mannose

Glycosidic Linkages

• Monosaccharide Linkage: The monosaccharide units are linked by a 1→4 glycosidic linkage in:

  • (A) Maltose
  • (B) Sucrose
  • (C) Cellulose
  • (D) Cellobiose

• Non-Reducing Sugar: Which of the following is a non-reducing sugar?

  • (A) Isomaltose
  • (B) Maltose
  • (C) Trehalose
  • (D) Lactose

• Reducing Sugar: Which of the following is a reducing sugar?

  • (A) Sucrose
  • (B) Trehalose
  • (C) Isomaltose
  • (D) Agar

• Disaccharide with 1,1-glycosidic Linkage: A disaccharide formed by 1,1-glycosidic linkage between their monosaccharide units is:

  • (A) Lactose
  • (B) Maltose
  • (C) Sucrose
  • (D) Arabinose

Major Sugar of Insect Hemolymph

• Major Sugar: The major sugar of insect hemolymph is:
  • Options:
    (A) Glycogen
    (B) Pectin
    (C) Trehalose
    (D) Sucrose

Conclusion

These notes encompass fundamental concepts related to carbohydrates, including definitions, classifications, characteristics, and specific examples of sugars and their roles in biological systems.