Ch. 23 Review Flashcards
List the 6 major activities involved in the processing of food
- Ingestion
- Mechanical Breakdown
- Propulsion
- Digestion
- Absorption
- Defecation
These activities are the functions of the digestive system.
What are the layers of the alimentary canal?
- Mucosa
- Submucosa
- Muscularis externa
- Serosa
The mucosa layer includes epithelium, lamina propria, and muscularis mucosae.
Describe the mucosa layer of the alimentary canal.
The mucosa consists of:
* Epithelial lining (simple columnar)
* Lamina propria (loose areolar CT)
* Muscularis mucosae (smooth muscle)
Functions include secretion, absorption, and protection.
What is the tissue type of the submucosa?
Areolar connective tissue
The submucosa is highly vascular and contains blood and lymph vessels.
What are the two major layers of the muscularis external?
- Inner Circular layer
- Outer Longitudinal layer
The inner circular layer can thicken to form sphincters.
What is the tissue type of the serosa?
Areolar connective tissue covered with mesothelium
The serosa is also known as the visceral peritoneum.
What epithelial tissue type is found in the mouth?
Stratified squamous epithelium
It is keratinized in some areas.
What type of epithelium is found in the stomach?
Simple columnar epithelium
All cells in the stomach are secretory.
What are the names of the sphincters in the digestive system?
- Lower esophageal sphincter (cardiac sphincter)
- Pyloric sphincter
- Ileocecal sphincter
- Hepatopancreatic sphincter
These sphincters control food passage and secretion.
What adaptations does the stomach have to its muscularis externa?
It has an additional oblique muscle layer
This aids in breaking down food and moving it to the small intestine.
What is the primary function of gastric mucous neck cells?
To produce thin mucus that protects the stomach lining
This mucus protects against gastric acid.
What hormone controls the secretion of gastric juices?
Gastrin
It regulates HCl secretion and digestive enzymes.
What are the phases of gastric secretion regulation?
- Cephalic phase
- Gastric phase
- Intestinal phase
Each phase has distinct triggers and effects on gastric secretion.
What is the major type of motility in the stomach?
Peristalsis
It aids in mechanical breakdown and propulsion of chyme.
What are the three major modifications of the small intestine wall?
- Circular folds
- Villi
- Microvilli (brush border)
These structures increase surface area for absorption.
What is the role of the simple columnar absorptive cells in the small intestine?
To absorb nutrients and electrolytes from digested food
These cells are primarily found in the epithelial villus mucosa.
What do intestinal crypts secrete?
Intestinal juice (water with mucus)
They help absorb nutrients and contain various cell types.
What are the two types of motility found in the small intestine?
- Segmentation
- Peristalsis
Segmentation mixes chyme, while peristalsis moves food residue towards the large intestine.
What is the main digestive role of the liver?
To produce bile
Bile helps emulsify fats.
What are the three functions of hepatocytes?
- Glycogen storage
- Protein production
- Detoxification
They metabolize and inactivate various compounds.
What is the function of the gall bladder?
To store excess bile
It releases bile into the small intestine when needed.
What are the major functions of pancreatic juice?
Contains enzymes that breakdown all categories of food
Produced by acinar cells.
Describe the unique structural features of the large intestine.
- Teniae coli
- Haustra
- Epiploic appendages
These structures contribute to the function and appearance of the large intestine.
What is the gastroileum reflex?
Caused by stomach activity and gastrin release leading to increased ileum segmentation
It helps push food residues into the large intestine.
What is the role of the mucosa in the large intestine?
To secrete mucus for food passage and protect the wall
The mucosa consists of simple columnar epithelial cells with goblet cells.
What are the two types of movements in the large intestine?
- Haustral contractions
- Mass movements
These movements help propel contents towards the rectum.
What triggers the defecation reflex?
Mass movements pushing feces into the rectum
This involves both involuntary and voluntary control.
Which anal sphincter is under voluntary control?
External anal sphincter
This allows for conscious control over defecation.
Where does chemical digestion occur for proteins?
Stomach and small intestine
Enzymatic digestion is crucial for protein breakdown.
What is the function of amylase?
Digests carbohydrates (starches)
Amylase is produced in the mouth and small intestine.
What is the role of maltase?
Digests carbohydrates (maltose)
Maltase is produced in the small intestine (brush border).
What is the function of lactase?
Digests carbohydrates (lactose)
Lactase is also produced in the small intestine (brush border).
What is the function of Amylase and where is it produced?
Digest carbohydrates (starches); produced in mouth and small intestine (pancreas)
Amylase is crucial for breaking down starches into simpler sugars.
What is the function of Maltase and where is it produced?
Digest carbohydrates (maltose); produced in small intestine (brush border)
Maltase specifically targets maltose, a disaccharide.
What is the function of Lactase and where is it produced?
Digest carbohydrates (lactose); produced in small intestine (brush border)
Lactase is essential for lactose digestion in dairy products.
What is the function of Lipase and where is it produced?
Digest lipids (fatty acids and triglycerides); produced in mouth, stomach, and small intestine (pancreas)
Lipase is critical for the digestion of dietary fats.
What is the function of Pepsin and where is it produced?
Digest proteins; produced in stomach, pancreas, and small intestine (brush border)
Pepsin is activated in the acidic environment of the stomach.
What is the function of Trypsin and where is it produced?
Digest proteins; produced in small intestine (from pancreas)
Trypsin is a key enzyme for protein digestion in the small intestine.
Match the disorder with its description: Constipation.
When food remains in the colon for extended periods, too much water is absorbed and the stool becomes hard and difficult to pass
Constipation can lead to discomfort and requires dietary adjustments.
Match the disorder with its description: Heartburn.
A burning, radiating substernal pain that occurs when stomach acid regurgitates into the esophagus
Heartburn is often exacerbated by certain foods and positions.
Match the disorder with its description: Diarrhea.
Any condition that rushes food residue through the large intestine without sufficient time to absorb remaining water; usual cause is irritation of the colon by bacteria
Diarrhea can lead to dehydration if not managed properly.
Match the disorder with its description: Gastric ulcers.
An erosion of the stomach wall usually caused by Helicobacter pylori bacteria which burrow through the stomach mucus
Gastric ulcers can cause significant pain and require medical treatment.
Match the disorder with its description: Appendicitis.
Acute inflammation resulting from a blockage that traps infectious bacteria in its lumen
Appendicitis is a medical emergency that often requires surgery.
Label the following layers of the alimentary canal:
A. Mucosa
A1. Epithelium
A2. Lamina propria
A3. Muscularis mucosae
B. Submucosa
C. Muscularis externa
D. Serosa
Identify the following structures of the stomach:
A. cardiac region
B. Fundus
C. Body
D. Pylorus
E. Pyloric sphincter /valve
F. Rugae
G. Longitudinal musclularis
H. Circular muscularis
I. Oblique muscularis
Cardiac region I
Fundus H
Body D
Pylorus F
Pyloric sphincter /valve G
Rugae E
Longitudinal musclularis A
Circular muscularis B
Oblique muscularis C
. Label the following structures:
Esophagus ______
Duodenum ______
Transverse colon ______
Liver ______
Gall bladder ______
Pancreas ______
Duodenum ______
Bile duct ______
Pancreatic duct ______
Hepatopancreatic ampulla ______
Hepatopancreatic sphincter ______
Duodenal papilla ______
Label the following structures:
Esophagus ______
Duodenum ______
Transverse colon ______
Label the following structures:
Esophagus ___A___
Duodenum ___E___
Transverse colon ___C__
Liver ______
Gall bladder ______
Pancreas ______
Duodenum ______
Bile duct ______
Pancreatic duct ______
Hepatopancreatic ampulla ______
Hepatopancreatic sphincter ______
Duodenal papilla ______
Liver __H____
Gall bladder __G____
Pancreas __J____
Duodenum __E___
Bile duct ___I___
Pancreatic duct __M____
Hepatopancreatic ampulla ___L___
Hepatopancreatic sphincter ___ L ___
Duodenal papilla __K____
Label the following structures of the large intestine:
Label the following structures of the large intestine:
Cecum F
Appendix E
Ascending colon G
Transverse colon A
Descending colon B
Sigmoid colon C
Rectum D
Anal canal H
