Digestive System 🍎

• Digestive system is used for ingestion, breakdown and absobtion of foods
• Mouth:

  • Breaks down food
  • food dissolved in saliva
  • Salivary amylase (salvatory glands) --> starch --> maltose
• Oesophagus:

  • transports food from the mouth to the stomach
• Stomach:

  • Stores large quantities of food
  • Absorbs certain drugs and alcohol
  • Produces chyme
  • Pepsin (gastric glands) --> hemoglobin --> polypeptides
• Small intestine:

  • Muscular contraction to churn food
  • Absorbs simple sugars, amino acids, fatty acids, glycerol, vitamins and water through the villi.
  • Protease --> amino acids --> glycerol
  • Amylase --> Starch --> fatty acids
  • Lipase --> triglycerides --> peptides
• Large intestine:

  • Absorbs water and vitamins: stores feces; defecation
• Proteins build and repair muscles and bones and to make hormones and enzymes.
• Carbohydrates act as an energy source and help to control blood glucose and insulin metabolism.
• Lipids help control what goes in and out of the cell.
• Vitamins help to fight infection wound healing, strengthening bones and regulating hormones.
• The lymphatic system maintains normal fluid levels in the body and absorbs fats, and fat-soluble vitamins so they can enter the bloodstream.
• Mechanical digestion involves physically breaking down food substances into smaller particles to more efficiently undergo chemical digestion.
• The role of chemicala digestion is to further degrade the molecular structure of the ingested compounds by digestive enzymes.
• The dental formula denotes the number of teeth arranged in a particular manner on one side of the mouth. It is written in such a way that it represents the arrangement of teeth in both lower and upper jaws. An adult human being has 2 incisors, 1 canine, 2 premolars and 3 molars on each half of the jaw.
• Mechanical digestion in the mouth happens when grinding food into smaller pieces by teeth, a process called mastication.
• Mechanical digestion in the stomach happens by peristaltic contractions of the smooth muscle and the churning of food.
• Mechanical digestion in the small intestine happens when the muscles mix food with digestive juice from the pancreas, liver and intestine.
• Chemical digestion in the mouth happens when salivary glands release saliva which contains digestive enzymes.