Digestive System

• The main function of the Digestive system is to convert complex food molecules into simpler molecules
• The largest organ that produces bile for digestion is the Liver

  
• The organ that serves as the passageway of food from the pharynx(throat) to the stomach is the Esophagus

  
• The organ that obtains nutrients from the food that we eat using tiny projections called villi is the Small intestine

  
• The organ that serves as temporary storage of food that we eat is the Stomach
• What happened to the food you ate today?

  1. Ingestion

  2. Digestion

  3. Absorption

  4. Assimilation

  5. Excretion
• Major Parts and Accessory Organs of Digestive System

  • Mouth
  • Esophagus
  • Stomach
  • Small Intestine
  • Large Intestine
  • Rectum
  • Anus
  • Liver
  • Gall bladder
  • Pancreas

  
• Mouth


  • Serves as the entrance of food in our body
  • Teeth mechanically break down food into small pieces
  • Tongue contains the taste buds and mixes food with saliva
  • Salivary glands releases the enzymes needed for digestion in the mouth
  • Epiglottis is a flap-like structure that closes over the trachea preventing food from entering it
• Esophagus


  • It is a long tube of smooth muscle
  • It moves the food from the throat to the stomach through peristalsis (a series of wave-like muscle contractions)
  • The chewed clump of food that passes through this is called BOLUS

  
• Stomach


  • It is a J-shaped muscular bag that stores the food we eat and break it down into smaller pieces
  • It contains digestive juices that has enzymes that further digest the food
  • It contains hydrochloric acid (HCl) that kills bacteria in the food that we eat
  • The digested food in the stomach is now called CHYME

  
• Small Intestine


  • It is roughly 22 feet long
  • Parts include: Duodenum, Jejunum, and Ileum
  • Villi are fingerlike projections covering surface of small intestine and it is where absorption of nutrients occurs

  
• Large Intestine


  • It is about 5 feet long and is also known as colon
  • It is responsible for absorption of water from the indigestible residue of food
  • It is a home to trillions of bacteria that is important in producing vitamins and controlling the growth of harmful bacteria
  • Parts include: Rectum and Anus
• Accessory Organs


  • Liver - Produces bile that acts as a detergent, dissolving droplets of fats from food
  • Gall bladder - Stores bile from the liver and delivers bile when food is digested
  • Pancreas - Produces digestive enzymes to digest fats, carbohydrates and proteins, and regulates blood sugar by producing insulin
• Tracing the pathway of food in our body

  1. Mouth

  2. Esophagus

  3. Stomach

  4. Small Intestine

  5. Large Intestine

  6. Rectum

  7. Anus

  
• When you swallow the food without chewing it, it can disrupt the proper sequence of the digestive process
• The organ that regulates the sugar level in our body is the Pancreas
• The organ that serves as the entrance of the food that we eat is the Mouth
• The organ that absorbs water from the undigested material is the Large Intestine
• The organ where feces are excreted or move out from our body is the Anus
• Digestion is the breakdown of complex food substance into simpler substance for energy, growth and cell repair
• The 6 Essential Nutrients

  • Carbohydrates
  • Proteins
  • Fats
  • Vitamins
  • Minerals
  • Water
• Digestion of Food


  1. Ingestion

  2. Mechanical breakdown

  3. Chemical digestion with saliva

  4. Peristalsis in esophagus

  5. Storage and chemical digestion in stomach

  6. Chyme passes through small intestine for final digestion

  7. Absorption of nutrients

  
• Cholecystectomy is a surgery used to remove the gall bladder with stones, so people who undergo this treatment should take in less fatty foods
• Chyme


  Digested food from the stomach
• Digestion in the stomach

  1. Churning and mixing food

  2. Breaking food into smaller pieces
• Digestion in the small intestine

  1. Mechanical digestion (Peristalsis)

  2. Chemical digestion

  
• Bile


  Secretion of the liver for digestion

  
• Pancreas


  Secretion for digestion
• Carbohydrate is broken down into glucose by the enzyme amylase
• Protein is broken down into amino acids by the enzyme pepsin
• Fats are emulsified into fat globules by bile, and then further broken down into fatty acids and glycerol by the enzyme lipase
• Cholecystectomy


  Surgery to remove the gallbladder with stones
• People who have undergone cholecystectomy


  Should take in less of certain foods
• Ingestion


  The process of taking in food
• Digestion


  The process of breaking down food from complex substances into simpler substances
• Absorption


  The process wherein digested food are absorbed
• Assimilation


  The process where nutrients are synthesized into the bloodstream and transported to cells
• Excretion

  The removal of waste and excess water from the body
• Diarrhea is characterized by loose, watery and frequent bowel movements
• Constipation is characterized by hard, compact stool