What are carbohydrates?

• Carbohydrates are organic compounds made of carbon (C), hydrogen (H), and oxygen (O).
• They are the main source of energy for the body.
• Often called sugars or saccharides.

Types of Carbohydrates

1. Monosaccharides (Simple sugars)
   • Single sugar units
   • Example: Glucose, Fructose, Galactose
   • Quick source of energy
2. Disaccharides
   • Two monosaccharides joined together
   • Example: Sucrose (Glucose + Fructose), Lactose, Maltose
3. Polysaccharides (Complex sugars)
   • Long chains of monosaccharides
   • Example: Starch (plants), Glycogen (animals), Cellulose (plants), Chitin (animals)
   • Provide long-term energy storage or structural support

Functions of Carbohydrates

1. Energy Source
   • Glucose is the primary energy source for cells.
2. Energy Storage
   • Starch in plants and glycogen in animals store energy.
3. Structural Role
   • Cellulose forms plant cell walls; chitin forms exoskeletons of insects.
4. Other Roles
   • Part of nucleotides (DNA/RNA) and cell signaling molecules.

In short:
Carbohydrates are sugars and starches that provide energy, store energy, and give structural support in living organisms.