The Digestive System Flashcards
Alimentary Canal
- an open tube at both ends, found in the digestive system
Mouth - Hard + Soft Palate, Uvula, Frenulum, Papillae
- Hard Palate = bony plate that forms the anterior part of the roof of the mouth
- Soft Palate = muscular structure forms the posterior part of the roof of the mouth
- Uvula = hangs from the roof of the mouth to prevent food and drink from entering the nasal cavities
- Frenulum = anchors the tongue to the floor of the mouth
- Papillae = “bumps” on the tongue act as sensory receptors for food and drink
Saliva
- helps to neutralize the acid produced by mouth bacteria
- starts the breakdown of carbohydrates (via enzyme salivary amylase)
- thins and lubricates what we eat
Parotid Glands
- located where the jaw and ear meet.
Submandibular Glands
- located at each side of the lingual frenulum
Sublingual Glands
- found at the anterior floor of the mouth
Caries + Gingivitis + Periodontitis
- C = cavities due to the breakdown of tooth enamel
- G = inflammation of the gums
- P = severe gingivitis and inflammation of the periodontal membrane
Oral Candidiasis (thrush)
- a yeast infection
- from antibiotics or asthma inhalers
Oral Cancer
- risk factors are alcohol/tobacco consumption, genetics, and oral sex
Esophagus
- a muscular tube that’s lined with mucus, connects the pharynx to the stomach
Upper and Lower Esophageal Sphincter
U = located at the superior end of the esophagus
- to prevent air from entering the esophagus due to
respiration
L = inferior end of the esophagus
- to prevent acidic stomach contents from leaving the
stomach
Gastroesophageal Reflux Disease GERD
- Chronic heartburn
Stomach + Chyme
- muscular walls contract, churning and mixing stomach contents with gastric juice
- Chyme = partially-digested semisolid mixture
Divisions of the Stomach
- Fundus = superior part
- Body = large, central section
- Pylorus = inferior, narrow portion
Pyloric Sphincter = separates stomach from the opening into the small intestine- allows stomach contents to hang around for a
while, promoting further chemical digestion
- allows stomach contents to hang around for a
Gastritis
- inflammation of the stomach
Gastric Ulcer
- Erosion of the stomach lining, often due to the use of NSAID drugs or infection by H. Pylori.
Stomach Cancer
- associated with alcohol/tobacco consumption, preserved foods and infection with Helicobacter Pylori
Small Intestine
- pancreas and liver produce pancreatic juice and bile to empty into the small intestine
Peristalsis + Villi
- layer of smooth muscle, the rhythmic contractions of which (peristalsis) move whatever’s been consumed along its length, toward the large intestine
V = projections that contain blood capillaries and lacteals that contain microvilli.- provide an enormous surface area so nutrients can
be absorbed: blood capillaries take up the
carbs and proteins, and lacteals take up fats.
- provide an enormous surface area so nutrients can
Liver
- liver is the largest visceral organ and has over 300 functions
- produces bile, a substance that contains cholesterol, and bile salts (important for fat digestion and transportation)
- converts excess glucose into GLYCOGEN, which is converted back to glucose, when needed, by the pancreatic hormone GLUCAGON
Jandice
- Yellowing of the skin, tongue, and eyes due to bile backing up into the bloodstream
Hepatitis
- inflammation of the liver
Cirrhosis
- liver damage resulting in the accumulation of fatty or fibrous tissue
Gallbladder
- stores and concentrates bile that’s produced by the live
- secretory function of the gallbladder is initiated by the presence of fat-containing chyme
Gallstones
- Masses of cholesterol; crystallized bile
Pancreas
- excretes pancreatic juice to neutralize acids in chyme before it enters the small intestine
- as well as enzymes that assist in breaking down fats, proteins, and carbs
Pancreatitis
- inflammation of the pancreas
- in severe cases, the pancreas digests itself
Large Intestine
- Chyme has lost much of its water and nutrients by the time it enters the large intestine
- work continues, with help from gut bacteria (the intestinal microbiome), which also plays a role in vitamin synthesis.
- Eventually, the contents of the large intestine become feces
Process of Large Intestine
- cebum
- acending colon
- transverse colon
- decending colon
- sigmond colon
- rectum
- anal canal
- anus
Vermiform Appendix
- hangs off of the cecum
- serves as a reservoir for bacteria of the intestinal microbiome, so disrupted colonies in the large intestine can be replenished when needed
Appendicitis
- inflammation of the appendix
- severe cases can involve rupture
Diarrhea
- colon emptying before water has been adequately absorbed from fecal matter
Constipation
- feces spend too much time in the colon, and become too dry.
Colitis
- inflammation of the colon
Colorectal Cancer
- associated with high consumption of red meat, and low fibre intake
