Digestive System Quiz Flashcards
What are the two main parts of the digestive system?
Alimentary canal
Accessory organs
What makes up the Alimentary Canal?
Mouth Pharynx Esophagus Stomach Intestines
What are the Accessory Structures?
Liver Pancreas Gall Bladder Teeth Salivary glands
What things occur in the digestive system?
- Propulsion(peristalsis)
- Mixing
- Secretion
- Digestion
- Absorption
- Elimination
What are the layers of the digestive tract?
- Mucosa
- Submucosa
- Muscularis
- Serosa/Adeventitia
What is mucosa?
lining epithelium of glandular tissue w/ lamina propria(vascular supporting loose connective tissue)
What is submucosa?
larger blood vessels
lymphatics
nerves
mucous secreting glands
What is muscularis?
inner circular
outer longitudinal
used in peristalsis
What is the Serosa or Adventitia?
outermost layer of loose connective tissue covered by viseral peritoneum, contains blood vessels, lymphatics, and nerves
What type of tissue lines the oral cavity?
stratified squamous epithelium
What are the functions of the oral cavity?
begin mechanical and chemical digestion
What is the soft palate?
classes off nasal passage and airway during swallowing, protects the nasal passage during sneezing by diverting to the mouth
What is the hard palate?
ridges grip food, rigid support for nasal cavity so that pressure in mouth doesn’t close off nasal passage
What are the three paired major salivary glands?
parotid- serous
submandibular- seromucous
sublingual- mucous
What controls salivation?
The autonomic nervous system
- Parasympathetic promotes salivation
- Sympathetic decreases salivation
What is the difference between salivation at rest and at stimulation?
Rest- 2/3 in submandibular
Stimulation- 50% in parotid
What are in salivary enzymes?
Salivary amylase
Lingual lipase
What are the types of teeth?
Incisors 8 Canines 4 Premolars 8 Molars 8 Wisdom teeth 4
What are the parts of the tooth?
Crown - Above the gingiva Root - Below the gingiva - anchored in bone
What are the four materials that make up the teeth?
Enamel
Dentin
Cementum
Pulp
What is enamel?
Covers crown
Hardest substance in body
What is dentin?
Under enamel
Much softer
What is cementum?
Covers the root of tooth
What is pulp?
Center of tooth (root canal)
Contains nerves and blood vessels that supply the tooth with sensations
What is the pharynx?
area behind nose and mouth
What is the function of the pharynx?
respiratory and digestive
What are the three sections of the pharynx?
- Nasopharynx
- Oropharynx
- Laryngopharynx
What is the epiglottis?
small, movable “lid” just above the larynx that prevents food and drink from entering your windpipe
What tissue lines the stomach and beyond?
simple columnar epithelium
What is the esophageal hiatus?
opening in the diaphragm through which the esophagus and the vagus nerve pass
What are the esophageal sphincters?
Upper (UES)
-Forms a barrier between esophagus and pharynx
Lower (LES)
-Cardiac/Gastroesophageal sphincter
What is a hiatal hernia?
upper part of the stomach bulges up through the hiatus, pushes stomach acids into esophagus
What are the four sections of the stomach?
- Cardiac
- Fundus
- Body
- Pylorus
What holds the stomach in place?
Lesser omentum
- liver to lesser curvature
Upper omentum
- greater curvature to transverse colon
What are the layers of muscle in the stomach?
- Longitudinal
- Circular
- Oblique
What are rugae?
ridges produced by folding of the wall of an organ
What lines/protects the stomach?
Alkaline mucus
What cells are involved in gastric gland secretion?
- Parietal cells
- Chief cells
- Mucous Neck Cells
- Enterendocrine (G) Cells
What do parietal cells produce?
HCl - denatures proteins, kills bacteria
Intrinsic Factor - necessary for B12 absorption
What do chief cells produce?
Pepsinogen
What do mucous neck cells produce?
Secrete acidic mucous
What do enteroendocrine (G) cells produce?
Secrete hormones, including gastrin
What is gastrin?
Peptide hormone, stimulates gastric acid secretion (HCl)
HCl causes pepsinogen to convert to pepsin for pepsin to break down proteins
Aids in peristalsis
What are the three phases of gastric secretion?
- Cephalic (brain)
- Gastric (3-4 hours in stomach)
- Intestinal (duodenum
How does the stomach go through mechanical digestion?
Mixing wave caused by muscles, gradually intensifying towards pylorus eventually creating chyme
How does the stomach go through chemical digestion?
- Salivary amylase
- Chyme
- Gastric lipase
- HCl
- Pepsin
- Rennin
What are the functions of the liver?
- Stores glycogen, vitamins, and minerals
- Nutrient conversion
- Detoxification
- Removes ammonia
- Blood protein synthesis
- Bile production = cholesterol+hemoglobin
What is the process of bile secretion?
Hepatocytes -secrete bile Canaliculi -send bile to hepatic ducts Hepatic ducts -adds bile acids, cholesterol, and organic molecules Gallbladder -5x concentration
What are the ducts of the liver?
Right+left hepatic ducts= common hepatic
Common hepatic+cystic duct= common bile duct
Cystic duct connects gallbladder to common bile duct
What are the lobes of the liver?
- Left
- Right
- Caudate
- Quadrate
What is the function of the gall bladder?
store and concentrate bile
What is the cystic duct?
joins gallbladder to common hepatic duct
What does bile do?
Critical for digestion and absorption of fats and fat-soluble vitamins in small intestine
What are the endocrine glands of the pancreas?
Hormone production
- Insulin
- Glucagon
What are the exocrine glands of the pancreas?
digestive enzymes
What are the 3 sections of the small intestine?
duodenum
jejunum
ileum
How long is the small intestine?
22-25 feet
What is the duodenum?
first section of the small intestine, shortest, contains duodenal glands, pancreatic secretions, and bile
What does the duodenum do?
chemically digests chyme to prepare it for absorption in small intestine
What is the jejunum and ileum?
absorbs nutrients from food using finger-like projections called villi
What is the ileocecal valve?
sphincter between ileum and colon
What does the vermiform appendix do?
aids in immune function and harbors bacteria
What does the large intestine include?
cecum, colon, rectum
How long is the large intestine?
5 feet
What does the large intestine do?
Absorbs water
contains digestive bacteria
Vitamin k2 production
What are the four parts of the colon?
- Ascending
- Transverse
- Descending
- Sigmoid
What is the rectum?
muscular tube with three valves to separate feces from gas
What is the anal canal?
inner and outer sphincters for defecation
How are the colon and large intestine different?
The colon does not include the cecum, appendix, rectum, or anal canal
What are haustra?
small pouches caused by sacculation, make the colon look segmented
What are haustral contractions?
slow segmenting movements occurring every 25 minutes
What are Taenia coli?
visible ribbons of smooth muscle on external surface of colon
What are Epiploic Appendages?
Pouches of peritoneum filled with fat along the colon, absent in the rectum
What is the Mesentery?
Set of tissues attaching intestines to posterior abdominal wall, formed by double fold of peritoneum that stores fat and allows vessels and nerves to supply the intestines
What does insulin do?
lower blood sugar level
What does glucagon do?
raises blood sugar level
What separates the left and right lobes of the liver?
falciform ligament
What liver lobe wraps around the inferior vena cave?
caudate lobe
What liver lobe wraps around the gallbladder?
quadrate lobe
What is the sphincter of Oddi?
controls release of bile, dysfunction can backup digestive juices and cause sever abdominal pain
What does salivary amylase do?
breaks starch into sugar, 30% of starch digestion in mouth
What does lingual lipase do?
breaks medium and long-chain fats into smaller pieces
How much liquid is pushed out at a time to the small intestine?
2ml
