SCIENCE -Structures and Functions of the Digestive System- 8

• The digestive system is composed of different organs that work together to break down food and nourish the body

  
• Digestion


  The breakdown of organic compounds into their simple forms for use by the cells
• Digestion


  1. Ingestion

  2. Mechanical digestion

  3. Chemical digestion

  4. Absorption

  5. Assimilation

  6. Excretion

  
• The digestive system involves important processes in order to carry out its function

  
• The cells in the body need food for energy used for growth and repair
• Food must be broken down into a form that these microscopic cells can use
• The body changes food into a usable form by means of a group of organs referred to as the digestive system

  
• 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

  
• Jejunum


  Second part of the small intestine where absorption of nutrient particles occurs
• Absorption


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

  
• Assimilation


  Movement of digested food nutrients into the blood vessels of the small intestine and use of nutrients by body cells

  
• Ileum


  Third part of the small intestine that assimilates B12 and reabsorbs conjugated bile salts
• Large intestine


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

  
• Egestion


  Release of undigested food collected in the rectum (feces) 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