human digestion

• Mechanical digestion


  Breaking down food into smaller pieces through physical processes like biting, chewing, and crushing
• Chemical digestion


  Breaking down large food molecules into smaller molecules that can be absorbed by the body, using enzymes
• Breaking down food


  1. Physical changes: Biting, chewing in the mouth, crushing in the stomach

  2. Chemical changes: Action of enzymes to break large molecules into smaller molecules
• Chewing or mastication


  Mechanically breaks down large food particles into smaller ones to prepare them for digestion
• Teeth


  • Specially adapted to cut, tear or grind/crush food
  • Digestion begins in the mouth, food is chopped into smaller pieces by the teeth and crushed by the flat teeth
  • Breaking food into smaller pieces allows digestive enzymes to penetrate it more easily
• Mechanical digestion


  • Chewing a saltine
  • Tongue breaking pieces of a hamburger apart
• Chemical digestion


  • Saliva breaking the saltine down into molecules of glucose
  • Pepsin (an enzyme) in your stomach breaking the hamburger into amino acids
• People get two sets of teeth during their lives: 20 milk teeth when young, replaced by 32 permanent teeth as they grow older
• Animals that swallow their food whole, like snakes, take much longer to digest it - up to 2 weeks for a large meal
• The digestive system runs from the mouth to the anus
• Teeth are very important but get treated poorly when neglected, they are part of a living thing
• Teeth are white, strong, but can be easily shaken, weakened, stained and dirtied; none were found at first, then one appeared, afterwards more are seen and thirty two appear at last, they all stand waiting for their prey (the food you eat)
• Types of digestion


  • Mechanical
  • Chemical
• Mechanical digestion includes chewing and swallowing
• Chemical digestion includes digestion of proteins, fats and carbohydrates