Download Digestive System PPT Notes

Learning Objectives
Introduction to
Medical Careers
Digestive System
Chapter 16
• Define at least 10 terms relating to the digestive
system
• Describe the four functions of the digestive
system
• Identify different structures of the digestive
system and their functions
• Identify the location and function of three
accessory organs of the digestive system
• Describe at least five disorders of the digestive
system
Vocabulary: Chapter 16
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Bile
Bolus
Chyme
Deglutition
Emesis
Endoscopy
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Enema
Flatulence
Ingestion
Jaundice
Mastication
Peristalsis
Sphincter
Villus
FACTS
approx. 30 feet long
unsterile- open at both ends
also called the ‘gastrointestinal system’
Functions
• Transportation of food & waste
• Physical & chemical breakdown of food
– physical=chewing, chemical=saliva
• Absorption of digestive food
– Nutrients your body wants
• Final elimination of waste
• Maintain proper balance of water
Organs
Mouth
• Teeth
– bite and chew food
(mastication)
• Tongue
– tastes, chews &
swallows food
• Saliva
– enzymes breakdown
food
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Esophagus
peristalsis- wave like
contraction by which food is
moved
Small
Intestine
• 23 feet long
• Longer in length and
smaller in diameter
• 3 parts
– Duodenum, Jejunum &
Ileum
• Continued secretion of
enzymes to breakdown
food
• Most absorption occurs
here
tube like structure,transports
food from mouth to
stomach via this
Stomach
• Sac like muscular organ
• Squeezes & churns food
to continue physical
breakdown
• Protein digestion begins
• Some items absorbed
into blood (alcohol,
glucose, drugs)
• 1-4 hours to empty into
small intestine
Duodenum, Jejunum & Ileum
• Lined with villi
• Fully breaks down food to nutrients to
send into bloodstream
• Transports the
mixture to large intestine
– carbs, fats, proteins
• Villi
– increase absorption area
Large Intestine
• 3 parts
– ascending colon
– transverse colon
– descending colon
• Absorbs into blood
– Water
– Vitamins
– Electrolytes
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Food Journey
(Anywhere from 3 hours to 3 days)
• Starts in mouth
• Through esophagus to stomach
• Stomach to Small Intestine (Duodenum to
Jejunum to Ileum)
• Large Intestine (Ascending colon to
Transverse to Descending)
• Out
Table 16-1 Digestive System
Accessory Organs of the Digestive
System
• Three accessory organs that aid in the
process of food breakdown
– Pancreas
• Exocrine and endocrine functions
– Produces pancreatic juice which helps break down
food
– Insulin & Glucagon: help regulate carbohydrate
metabolism
Accessory Organs of the Digestive
System
• Three accessory organs that aid in the
process of food breakdown
– Liver
• Produces bile to assist in digestion of fat
• Converts glucose to a storage form
• Stores the fat-soluble vitamins (A, D, E, and K)
– Gallbladder
• Stores bile until it is needed in the small
intestine
Assessment Techniques
• Radiography
• Uses barium to allow structures to show esophagus,
stomach, and small intestine
• Endoscopy
– Flexible tube inserted into body cavities
• Gastric analysis
– A nasogastric tube is used to remove stomach contents
• Fecal analysis
– Examination of stool specimen for presence of microorganisms or
blood
• Palpation and auscultation
– Feeling the abdomen and listening for bowel sounds
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Figure 16-3 Endoscopy
Disorders of the Digestive System
• Alactasia
– Also called “lactose intolerance.” Not enough
of the enzyme lactase is produced. The
unabsorbed lactose ferments in the intestines
leading to gas, cramps, and diarrhea.
• Appendicitis
– Inflammation of the appendix
• Cholecystitis
– Inflammation of the gallbladder
Disorders of the Digestive
System (Continued)
• Cirrhosis
– A chronic degenerative condition of the liver
accompanied by the formation of scar tissue
• Colon cancer
– An abnormal growth in the large intestine
• Constipation
– The inability to defecate
• Crohn’s disease
– Inflammation and ulceration, usually affecting
the ileum or colon, or both
Disorders of the Digestive
System (Continued)
• Gastritis
– Inflammation of the stomach lining
• Gastroesophageal reflux disease
– Frequent heartburn or chest pain, bitter
taste in the mouth, difficulty swallowing,
frequent hoarseness or coughing
• Halitosis
– Or bad breath, is caused by anaerobic
bacteria
Disorders of the Digestive
System (Continued)
• Diarrhea
– The passage of frequent and watery stools
• Diverticulitis
– The weakening of the colon wall, leading to
formation of a pouch, causing infection or
abscesses if fecal material trapped
• Food poisoning
– Illnesses transmitted by food
Disorders of the Digestive
System (Continued)
• Heartburn
– A painful burning sensation in the esophagus
caused by the backflow of acidic chyme from
the stomach
• Hemorrhoid
– A painful dilated vein in the lower rectum or
anus
• Hepatitis
– A viral infection of the liver
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Disorders of the Digestive
System (Continued)
• Mumps
– A highly contagious viral infection of the
parotid glands
• Pancreatitis
– A mild acute or chronic condition resulting
from gallbladder stone blockage, disease,
injury, or alcoholism
• Peritonitis
Disorders of the Digestive
System (Continued)
• Phenylketonuria
– Inherited disease that can lead to mental
retardation if untreated
• Pyloric stenosis
– A birth defect in which a constricted pyloric
sphincter does not allow food to pass
easily into the small intestine
– An inflammation of the abdominal cavity
caused by bacteria
Disorders of the Digestive
System (Continued)
• Tay-Sachs
– A recessive genetic disorder in which fat cells
accumulate in the body and cause damage to
normal cells
• Ulcer
– An open sore on the lining of the digestive
tract
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