Carbohydrates: Monosaccharides and Disaccharides

Monosaccharides

• Simple sugars, also known as simple carbohydrates
• Composed of a single sugar molecule
• Examples:
  • Glucose (C6H12O6)
  • Fructose (C6H12O6)
  • Galactose (C6H12O6)
• Characteristics:
  • Sweet taste
  • Soluble in water
  • Can be fermented by yeast

Disaccharides

• Composed of two sugar molecules bonded together
• Examples:
  • Sucrose (glucose + fructose)
  • Lactose (glucose + galactose)
  • Maltose (glucose + glucose)
• Characteristics:
  • Can be broken down into monosaccharides through hydrolysis
  • Soluble in water
  • Provide energy for the body

Polysaccharides

• Composed of three or more sugar molecules bonded together
• Examples:
  • Starch (plant-based)
  • Glycogen (animal-based)
  • Cellulose (plant-based)
• Characteristics:
  • Insoluble in water
  • Can be broken down into monosaccharides through hydrolysis
  • Provide energy storage for the body

Glycogen Synthesis

• Process of forming glycogen from glucose molecules
• Occurs in the liver and muscles
• Steps:
  1. Glucose phosphorylation to form glucose-6-phosphate
  2. Conversion of glucose-6-phosphate to glucose-1-phosphate
  3. Formation of glycogen from glucose-1-phosphate molecules
• Regulation:
  • Insulin stimulates glycogen synthesis
  • Glucagon inhibits glycogen synthesis

Cellulose Structure

• A type of polysaccharide composed of glucose molecules
• Found in plant cell walls
• Structure:
  • Long chains of glucose molecules bonded together through beta-1,4-glycosidic bonds
  • Chains are arranged in a crystalline structure
  • Hydrogen bonding between chains provides strength and rigidity
• Function:
  • Provides structural support and protection to plant cells
  • Indigestible by humans, but can be broken down by certain microorganisms

Monosaccharides

• Simple sugars, also known as simple carbohydrates, composed of a single sugar molecule
• Examples include glucose (C6H12O6), fructose (C6H12O6), and galactose (C6H12O6)
• Characteristics: sweet taste, soluble in water, and can be fermented by yeast

Disaccharides

• Composed of two sugar molecules bonded together
• Examples include sucrose (glucose + fructose), lactose (glucose + galactose), and maltose (glucose + glucose)
• Characteristics: can be broken down into monosaccharides through hydrolysis, soluble in water, and provide energy for the body

Polysaccharides

• Composed of three or more sugar molecules bonded together
• Examples include starch (plant-based), glycogen (animal-based), and cellulose (plant-based)
• Characteristics: insoluble in water, can be broken down into monosaccharides through hydrolysis, and provide energy storage for the body

Glycogen Synthesis

• Process of forming glycogen from glucose molecules
• Occurs in the liver and muscles
• Steps include glucose phosphorylation, conversion of glucose-6-phosphate to glucose-1-phosphate, and formation of glycogen from glucose-1-phosphate molecules
• Regulation: insulin stimulates glycogen synthesis, while glucagon inhibits it

Cellulose Structure

• A type of polysaccharide composed of glucose molecules
• Found in plant cell walls
• Structure: long chains of glucose molecules bonded together through beta-1,4-glycosidic bonds, arranged in a crystalline structure, and held together by hydrogen bonding between chains
• Function: provides structural support and protection to plant cells, and is indigestible by humans but can be broken down by certain microorganisms

This quiz covers the basics of monosaccharides and disaccharides, including their composition, examples, and characteristics.