Zusammenfassung der Ressource
Human Digestive System
- General Terms
- Digestion
- The physical and chemical process by which food is
broken down into smaller, soluble molecules that can be
absorbed into the bloodstream
- Physical digestion
- The mechanical action of teeth,
jaw and muscle movement
- Mouth
- Mastication
- Chewing using teeth and jaw movement
- Muscle
- Peristalsis
- Oesophagus
- Small intestine
- Contractions in
stomach wall
- Other
- Small intestine
- Bile emulsifying fat
- Breakdown of large food
molecules into smaller
molecules
- Increases surface area
- Increases efficiency of chemical digestion
- Chemical digestion
- Action of enzymes and gastric juices
- Mouth
- Amylase enzyme
- Stomach
- Gastric fluids
- Small intestine
- Pancreatic juice
- Enzymes
- Complex proteins
folded into specific
shapes
- Have an active site
- Only fits a specific substrate
- Helps break down large food molecules into
smaller, soluble molecules that can be absorbed
into the bloodstream by catalysing chemical
reactions in the digestive system
- Mouth
- Stomach
- Lined with gastric pits
- Produces gastric fluids
- Hydrochloric acid (HCl)
- Acidic (pH 1-2)
- Mucus
- Protects stomach lining from corrosive
nature of the HCl
- Pepsin
- A protease
- Catalyses the breakdown of proteins into polypeptides
- Liquifies the food into chyme
- Semi digested food
- Large, elastic walls
- Can hold 2-4 L of food
- Meal can be ingested quickly and
digested slowly
- Muscular contractions of
stomach walls
- Churns food
- Thoroughly incorporates food
with gastric fluids
- Small Intestine
- Large Intestine