Digestive system: its part and function

• There is much variety of life within and between organisms but the biochemical basis of life is similar for all living things
• Key molecules required to build structures that enable organisms to function

  • Carbohydrates
  • Proteins
  • Lipids
  • Nucleic Acids
  • Water
• Monomers


  Smaller units from which larger molecules are made
• Polymers


  Molecules made from a large number of monomers joined together in a chain
• Synthetic polymers


  • nylon
  • polyethylene
  • polyester
  • Teflon
  • epoxy
• Enzyme catalysis


  1. Substrate binding

  2. Transition state facilitation

  3. Catalysis

  4. Release
• Enzymes


  • They increase the rate of chemical reactions without themselves being consumed or permanently altered by the reaction
  • They increase reaction rates without altering the chemical equilibrium between reactants and products
• As temperature increases


  The rate of reaction increases
• Boxes on the game

  Represent parts of the digestive system

  
• Instructions beside the boxes

  Tell you about the digestive system

  
• Ingestion


  Taking in food or any substance into the body through the mouth

  
• Digestion


  1. Breaking down of large food molecules into smaller molecules for easy absorption by the cells

  2. Includes both chemical and mechanical digestion

  
• Mouth


  • Teeth cut, crush, and break food into tiny pieces
  • Tongue helps mix food with saliva forming a moist ball called bolus
• Saliva


  Contains salivary amylase that breaks down starch into smaller carbohydrates
• Peristalsis


  Wave-like muscle contractions that push and transport foods and liquids in small sections to the stomach
• Stomach


  1. shaped, bag-like muscular organ that stores food and turns it into chyme (semifluid material)
• Gastric juices


  Hydrochloric acid and pepsin that begin the chemical breakdown of proteins
• Organs that secrete essential substances

  • Liver
  • Pancreas
  • Gall bladder
• Bile


  Green fluid produced by the liver that turns large fat droplets into smaller ones and aids in fat digestion
• Pancreatic enzymes


  Amylase, peptidase, and lipase that aid in the digestion of carbohydrates, proteins, and fats respectively
• Small intestine


  Breaks down food further into substances like glucose that can be absorbed by the villi
• Duodenum


  First and shortest part of the small intestine that resumes chemical digestion and prepares for absorption
• Absorption


  Passing of soluble food molecules in the wall of the small intestine through the villi
• Villi


  Tiny, finger-like projections from the epithelial lining of the intestinal wall that increase surface area for absorption
• Assimilation


  Movement of digested food nutrients into the blood vessels of the small intestine through diffusion and use of nutrients into the body cells through the microvilli

  
• Microvilli


  Microscopic cellular membrane projections that expand the surface area for diffusion
• Large intestine


  Where reabsorption of liquid, electrolytes and some vitamins from the undigested food takes place

  
• Egestion


  Release of undigested food collected in the rectum called feces and pushed out of the body through the anus by defecation
• Scoring Rubrics:

  2 points - Discussions are complete with no misconception.

  1 point - Discussions are incomplete with minor misconception.

  0 point - There is no discussion shown.
• Illustrated by: Rosa Mia L. Pontillo