2.07-2.08 Remember the structures of the digestive system

DIGESTION The process of changing complex solid foods into simpler soluble forms which can be absorbed by body cells. BOLUS – soft, pliable ball – created from chewing and addition of saliva – it slides down esophagus PERISTALSIS – wavelike motions, moves food along esophagus, stomach and intestines

Peristalsis https://youtu.be/iv2_Inta1MQ?list=PLqqlrsiXHkNo8ySxB-6hOFSj09Z4JKI40

Structures of the digestive system Also known as: Alimentary Canal Digestive Tract Gastrointestinal Tract Upper GI Lower GI Over 30’ in length from mouth to anus

The Digestion Tract https://youtu.be/VwrsL-lCZYo?list=PLqqlrsiXHkNo8ySxB-6hOFSj09Z4JKI40

Structures of the digestive system Primary structures Mouth Esophagus Stomach Small intestines Large intestines Accessory structures Tongue Teeth Salivary glands Pancreas Liver Gall bladder 2.07 Remember the structures of the digestive system

Structures of the digestive system Mouth (buccal cavity) Tongue Teeth Salivary Glands Palate Uvula The physical breakdown of food begins here first…digestion begins in the mouth

Structures of the digestive system Tongue Attached to floor of mouth Made of skeletal muscle attached to four bones Taste buds on the surface Sweet Sour Bitter Salty

Structures of the digestive system Teeth Primary (deciduous) 20 “baby teeth” Secondary (permanent) 32 “adult teeth” Did you know??? Canine teeth are also known as cuspids and eye teeth. Teeth and tongue aid in physical / mechanical digestion of food

Structures of the digestive system Salivary glands Parotid gland Largest salivary gland Ptyalin in saliva converts starches to simple sugars causes the initial chemical breakdown. Submandibular gland Sublingual gland 2.07 Remember the structures of the digestive system

Structures of the digestive system Palate – separates the mouth from the nasal cavity Hard Soft Uvula Flap of skin hanging in the back of the throat 2.07 Remember the structures of the digestive system

Structures of the digestive system Pharynx (throat) Nasopharynx Oropharynx Hypopharynx 2.07 Remember the structures of the digestive system

Structures of the digestive system Esophagus Muscular tube, 10” long Connects the pharynx and stomach

Structures of the digestive system Stomach Upper left quadrant of the of the abdominal cavity Fundus Body Pylorus 2.07 Remember the structures of the digestive system

Cardiac sphincter - controls passage of food into stomach and keeps it from going back into the throat. PYLORIC SPHINCTER – valve, regulates the entrance of food into duodenum RUGAE – mucous coat lining of stomach in folds when the stomach is empty Stomach has muscular coat that allows it to contract (peristalsis) and push food into the small intestine 2 – 4 hours for stomach to empty

Structures of the digestive system Small intestines – main function is absorption of NUTRIENTS Duodenum First segment 12’ long Jejunum Second segment 8’ long Ileum Third segment 10-12’ long

Structures of the digestive system Large intestines Approximately 2” in diameter 5’ long Responsible for elimination of waste and absorption of water

Functions of the digestive system Teeth Define mastication. How is the tooth’s shape related to its function? Incisors Cuspids Bicuspids Molars 2.08 Understand the functions and disorders of the digestive system

Accessory Organs of Digestion PANCREAS Located behind stomach Exocrine function – secretes digestive enzymes to break down food. Also has endocrine function. Feather shaped organ

Functions of the digestive system Liver Produce and store glucose in the form of GLYCOGEN Detoxify alcohol, drugs and other harmful substances Manufacture blood proteins Manufactures bile Store Vitamins A, D and B complex Connects to gall bladder and small intestine by ducts

Functions of the digestive system Gallbladder Small muscular green sac that secretes and stores bile Located in the right upper quadrant of abdominal cavity. When fatty foods digested, bile released by gallbladder

Functions of the digestive system Large intestine CHYME – semi-liquid food and gastric juices Approx 2” in diameter Also called the colon CECUM – lower right portion of large intestine APPENDIX-blind sac attached to cecum, having no known function RECTUM – last portion of large intestine ANUS – external opening of the Lg. intestine

Disorders of the digestive system Anorexia Decreased or poor appetite Symptom Anorexia nervosa Eating disorder characterized by refusal to eat Psychiatric disorder Bulimia nervosa (binge eating and purging) is a psychiatric disorder as well VS Opposite disorder = obesity

Obesity is one of the common eating disorders in the United States. A person is considered obese if their BMI (body mass index is above 30. How to calculate BMI: BMI = ( lbs/inches² ) (weight in pounds * 703 ) ———————————— height in inches² BMI Weight Status Below 18.5 Underweight 18.5 -24.9 Normal 25 - 29.9 Overweight 30 & Above Obese

Disorders of the digestive system Caries Cavities How often should you brush and floss? Can you identify preventive measures? 2.08 Understand the functions and disorders of the digestive system

Disorders of the digestive system Cholecystitis Inflammation of the gall bladder Sx = pain that radiates to right shoulder…frequently after eating fatty foods How is it treated? - cholecystectomy Cholelithiasis – gall stones

Disorders of the digestive system Cleft palate Hard and/or soft palate doesn’t close completely during fetal development Problems swallowing Surgery needed to repair 2.08 Understand the functions and disorders of the digestive system

Disorders of the digestive system Cirrhosis Chronic, progressive disease of liver Normal tissue replaced by fibrous connective tissue. 75% caused by excessive alcohol consumption (also caused by Tylenol use)

Disorders of the digestive system Constipation When defecation delayed, feces become dry and hard Rx – diet with cereals, fruits, vegetables, (roughage), drinking plenty of fluids, exercise, and avoiding tension 2.08 Understand the functions and disorders of the digestive system

Disorders of the digestive disorders Diarrhea Loose, watery, frequent bowel movements when feces pass along colon too rapidly Caused by infection, poor diet, nervousness, toxic substances or irritants in food

Disorders of the digestive disorders Gastroenteritis Inflammation of mucous membrane lining of stomach and intestine Common cause = virus Sxs – nausea, vomiting, diarrhea for 24-36 hours Complication = dehydration Prevention…good handwashing

Disorders of the digestive system Gastroesophageal reflux disease (GERD) Reflux of gastric acid into the espohagus Sx – burning sensation that often worsens with laying flat…gets better with sitting up or raising head of bed

Disorders of the digestive system Hepatitis Acute Chronic Hepatitis A (contaminated food or water borne), B (blood borne), C (blood borne), D, E Which hepatitis virus has a vaccine? 2.08 Understand the functions and disorders of the digestive system

Disorders of the digestive system Irritable bowel syndrome Cause unknown Sx – abdmonial pain, bloating, diarrhea and constipation (alternating) Trt – lifestyle and diet changes, medication 2.08 Understand the functions and disorders of the digestive system

Disorders of the digestive system Chron’s Disease and Ulcerative Colitis Autoimmune disorders Type of inflammatory bowel disease Sxs – abdominal pain, severe diarrhea, malnutrition

Disorders of the digestive system Peptic ulcer - Sore or lesion that forms in the mucosal lining of the stomach Gastric ulcers in the stomach and duodenal ulcers in the duodenum Cause – H. pylori (bacteria) is primary cause Lifestyle factors that contribute: cigarette smoking, alcohol, stress, certain drugs

Relevance of nutrition to the digestive system Vitamins Fat soluble Vitamins A, D, E, K Water soluble Vitamins C, B Proteins aid in wound healing Carbohydrates such as bread and pasta offer quick energy Electrolytes Calcium Chloride Magnesium Phosphorus Potassium Sodium