Digestive System Flashcards
What is the serous membrane of the abdominal cavity?
Peritoneum
What are the 2 parts of the peritoneum?
- Visceral Peritoneum –> Surrounds digestive organs
- Parietal Peritoneum –> Lines the body wall
Give example of peritoneal organs and retroperitoneal organs
Peritoneal Organs: Stomach, intestine
Retroperitoneal Organs: Kidneys, Aorta, Inferior vena cava
What is the name of the peritoneal membrane attached to the small intestine?
mesentery
What is the name of the peritoneal membrane attached to the lesser curvature of the stomach?
lesser omentum
What is the name of the peritoneal membrane attached to the greater curvature of the stomach?
greater omentum
What is the name of the peritoneal membrane attached to the transverse colon?
transverse mesocolon
What is the name of the peritoneal membrane attached to the sigmoid colon?
sigmoid mesocolon
List the 4 layers of the wall of the alimentary canal and function of each layer
- Mucosa: Innermost layer
- Submucosa: External to mucosa; contains blood/lymphatic vessels, nerve fibers
- Muscularis Externa: External to the submucosa
- Serosa: Outermost layer
List the 4 layers of the wall of the alimentary canal and describe the tissue type
- Mucosa: epithelium layer
- Submucosa: connective tissue
- Muscularis Externa: Circular layer - deep ; longitudinal layer - superficial
- Serosa: visceral peritoneum
What does the term “digestion” mean?
Breakdown of macromolecules to their building blocks that’s water soluble
What are the 2 mechanisms by which digestion takes place?
- Mechanical breakdown –> Chewing/churning food in stomach
- Chemical Digestion –> Chemical reactions that involve enzymes to breakdown food
What are the sphincters/valves that control the movement of food between the esophagus and stomach?
cardiac sphincter
What are the sphincters/valves that control the movement of food between the stomach and small intestine?
pyloric sphincter
What are the sphincters/valves that control the movement of food between the small intestine and large intestine?
Ileocecal valve
What are the sphincters/valves that control the movement of food between the rectum and outside of the body?
Internal/external anal sphincter
What are the 3 types of gastric glands and what are their functions?
- Mucous Neck cells –> Secretes spinal mucus
- Parietal cells –> Secretes hydrochloric acid (HCl) and gastric intrinsic factor
- Chief cells –> Secretes pepsinogen
What are the 3 functions of the digestive system?
- Digestion
- Absorption
- Defecation
What is the function of digesiton?
Breakdown of macromolecules to their building blocks that’s water soluble
What is the function of absorption?
Transport of digested nutrients to blood
What is the function of defecation?
Elimination of indigestible substances as feces
Pain in the alimentary canal but there’s no bleeding. Where is the injury?
Injury to the mucosa
Pain in the alimentary canal and there’s bleeding. Where is the injury?
Injury to the submucosa
What is peristalsis?
Contraction and relaxation of the alimentary canal (longitudinal layer)
What is segmentation?
Rhythmic local contractions of the intestine in the circular layer
What are the 3 functions of the large intestine?
- Absorb water and electrolytes
- Eliminate waste and undigested material
- Mass peristaltic movements forces feces towards the rectum
What does micro flora do?
Host beneficial bacteria
What consists of the pharynx?
What is the membrane lining?
Oropharynx and laryngopharynx
stratified squamous epithelium
What consists of the esophagus?
What is the membrane lining?
Cardiac sphincter that joins the esophagus/diaphragm and stomach
- Mucosa is stratified squamous epithelium
What is the membrane lining of the stomach?
What does it do/secrete?
Membrane lining is simple columnar epithelium
Site of where food is churned into chyme; secretes pepsin for protein digestion
What consists of the small intestine?
What does it do/secrete?
Consists of: duodenum, jejunum, and ileum
Site of most enzymatic digestion and absorption; the duodenum is where pancreatic lipase and bile digest fat to make it water soluble
Membrane lining: simple columnar epithelium
What consists of the large intestine? (8)
What is the membrane lining?
- Cecum, appendix, ascending colon, transverse colon, descending colon, sigmoid colon, rectum, and anal canal
Membrane lining: simple columnar epithelial tissue
What consists of the rectum?
What is the membrane lining? (2)
Internal and external anal sphincter
Mucosa of Rectum: stratified squamous epithelium
Internal Anal Sphincter: Smooth muscle
External Anal Sphincter: Skeletal muscle
What are gastric glands?
Glands deep to the gastric pit
What are the 4 regions of the stomach?
- cardial part
- fundus
- body
- pyloric part
What are the 3 muscle layers in the stomach?
- circular layer
- longitudinal layer
- oblique layer
What 3 things help with absorption of the small intestine?
- circular folds
- villi
- microvilli
What are 2 disorders of the digestive system?
- gastric ulcers –> peptic ulcer in the pyloric region of the stomach
- duodenal ulcers –> caused by the Helicobacter pylori in the duodenum
What are circular folds?
transverse ridges of mucosa and submucosa
What is villi?
Fingerlike projections of mucosa
What does microvilli do?
Increases surface area for absorption
