Digestive system

    Cards (46)

    • Nutrition
      The life function of nutrition involves ingestion, digestion, and egestion
    • 6 Essential Nutrients
      • Water
      • Protein
      • Carbohydrates
      • Fats/Lipids
      • Vitamins & Minerals
    • Hydrolysis
      The process that water is necessary for
    • Food particles need to be small enough to diffuse into our cells
    • Mechanical digestion
      Teeth break down food into smaller pieces
    • Chemical digestion
      The enzyme salivary amylase begins the digestion of carbohydrates
    • Bolus
      The food after it has been broken down in the mouth
    • Peristalsis
      Muscle contractions within the walls of the esophagus that push the bolus to the stomach
    • Cardiac sphincter
      Valve between the esophagus and the stomach that closes to prevent food from moving back up the esophagus
    • Stomach
      • Mechanical digestion via muscle contractions
      • Chemical digestion of proteins carried out by the enzyme pepsin and stimulated by hydrochloric acid
      • Stomach lining coated with mucus to protect it from acid erosion
      • Food spends 1-2 hours in the stomach and it is turned completely into liquid, called chyme
    • Pyloric sphincter
      Valve that seals off the stomach from the small intestine and prevents the chyme from moving backwards into the stomach
    • Small intestine
      • Most chemical digestion occurs here (proteins, carbs, and lipids)
      • As the chyme moves through the small intestine, most nutrients are absorbed by the lining of the small intestine and enter the bloodstream
      • About one inch in diameter and 20 feet in length
    • Villi
      Fingerlike projections that line the inside of the small intestine and increase the surface area for absorption of nutrients
    • Bile
      Produced by the liver, it emulsifies (breaks down) fats so pancreatic lipases can do their job
    • Pancreas
      Produces enzymes and secretes them into the small intestine, also secretes bicarbonate to neutralize the acidic chyme
    • Large intestine
      • No digestion occurs here, excess water is absorbed
    • Rectum
      Where undigested food passes from the large intestine and is stored before being eliminated from the body via the anus
    • Constipation is when chyme moves too slowly through the large intestine and too much water is absorbed, resulting in difficulty egesting food
    • Diarrhea is when chyme moves too quickly through the large intestine resulting in the lack of water absorption
    • Ulcers
      The mucus lining in the stomach wears thin, allowing the hydrochloric acid in the stomach to burn the sensitive lining of the stomach wall
    • Jaundice
      A bile duct becomes blocked (typically due to a gallstone) and bile backs up into the liver, sometimes into the bloodstream causing yellowing of the skin and eyes
    • Gallstones
      Occur when bile crystallizes in the gallbladder, creating pebble-like deposits
    • Celiac disease
      Autoimmune disorder in which the body attacks the villi of the small intestine when gluten is ingested, preventing proper nutrient absorption
    • Nutrition
      The life function of nutrition involves ingestion, digestion, and egestion
    • 6 Essential Nutrients
      • Water
      • Protein
      • Carbohydrates
      • Fats/Lipids
      • Vitamins & Minerals
    • Water
      Necessary for hydrolysis
    • Food particles need to be small enough to diffuse into our cells
    • Mechanical digestion
      Teeth break down food into smaller pieces
    • Chemical digestion
      The enzyme salivary amylase begins the digestion of carbohydrates
    • Bolus
      The food after being broken down in the mouth
    • Peristalsis
      Muscle contractions within the walls of the esophagus that push the bolus to the stomach
    • Cardiac sphincter
      Valve between the esophagus and the stomach that closes to prevent food from moving back up the esophagus
    • Stomach
      1. Mechanical digestion via muscle contractions
      2. Chemical digestion of proteins carried out by the enzyme pepsin and stimulated by hydrochloric acid
      3. Stomach lining coated with mucus to protect it from acid erosion
      4. Food turned completely into liquid, called chyme
    • Pyloric sphincter
      Valve that seals off the stomach from the small intestine and prevents the chyme from moving backwards into the stomach
    • Small Intestine
      1. Chyme leaves the stomach and enters the duodenum
      2. Most chemical digestion of proteins, carbs, and lipids occurs here
      3. Most nutrients are absorbed by the lining of the small intestine and enter the bloodstream
    • Villi
      • Fingerlike projections that line the inside of the small intestine and increase the surface area for absorption of nutrients
      • Capillaries are found within each villus to allow diffusion of nutrients into the bloodstream
    • Bile
      Produced by the liver, emulsifies (breaks down) fats so pancreatic lipases can do their job
    • Pancreas
      • Produces enzymes and secretes them into the small intestine
      • Secretes bicarbonate to neutralize the acidic chyme entering the small intestine from the stomach
      • Produces trypsin, which digests proteins, and pancreatic amylase, which digests carbohydrates
    • Large Intestine
      No digestion occurs here, excess water is absorbed
    • End of the Journey
      1. Undigested food passes from the large intestine to the rectum, where it is stored
      2. Waste is eliminated from the body via the anus