Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
33 Cards in this Set
- Front
- Back
Which type of epithelium lines the oral cavity?
|
stratified squamous epithelium
|
|
The digestion of which nutrient would be affected by damage to the parotid salivary glands?
|
carbohydrates
|
|
Which type of tooth is most useful for chopping off bits of relatively rigid foods?
|
incisors
|
|
What is unusual about the muscularis externa of the esophagus?
|
-it contains skeletal muscle cells along most of its length
-it is surrounded by an adventitia rather than a serosa |
|
Where in the human body would you find the fauces?
|
the fauces is the opening between the oral cavity and the pharynx
|
|
What is ocurring when the soft palate and larynx elevate and the glottis closes?
|
swallowing is ocurring
|
|
How does a large meal affect the pH of blood leaving the stomach?
|
stomach acid secreted for digestion takes hydrogen ions from the blood to be made, the blood leaving the stomach will have fewer and will have a higher pH
|
|
When a person suffers from chronic gastric ulcers, the branches of the vagus nerve that serve the stomach are sometimes cut to provide relief. Why might this work?
|
parasympathetic nerves can stimulate gastric secretions, even when food isn't present, cutting the nerve would prevent this and hopefully prevent more ulcers
|
|
The enzymatic breakdown of large molecules into their basic building blocks is called
|
chemical digestion
|
|
The outer layer of the digestive tract is known as the
|
serosa
|
|
Double sheets of peritonium that provide support and stability for the organs of the peritoneal cavity are the
|
mesentaries
|
|
Most of the digestive tract is lined by ___ epithelium
|
simple columnar
|
|
Regional movements that occur in the small intestine and function to churn and fragment the digestive material are called
|
segmentation
|
|
What are the 6 steps involved in digestion?
|
1-ingestion
2-mechanical processing 3-secretion 4-digestion 5-absorption 6-excretion |
|
Name and describe the layers of the digestive tract, proceeding from the innermost to the outermost layer.
|
-mucosa, epithelial layer, digestion and absorption of nutrients
-submucosa, connective tissue layer conatins lymphatic and blood vessels and the submucosal nerve plexus -muscularis externa, smooth muscle and the myenteric nerve plexus -serosa, outermost layer, epithelium and connective tissue form visceral peritoneum or adventitia |
|
What three basic mechanisms regulate the activities of the digestive tract?
|
neural mechanisms
hormonal mechanisms local mechanisms |
|
What are the three phases of swallowing, and how are they controlled?
|
buccal phase-voluntary
pharyngeal phase- involuntary esophageal phase- involuntary |
|
How is the epithelium of the stomach protected from digestion?
|
mucous secreted by epithelial cells, and nueral and hormonal control over the times and rates of acid secretion
|
|
How do the three phases of gastric secretion promote and facilitate gastric control?
|
-cephalic phase, sight or thought of food, directed by CNS, prepares stomach
-gastric phase, arrival of food in stomach, initiated by stomach distention, increase in pH, and presence of undigested materials -intestinal phase, chyme enters intestine, controls rate of gastric emptying so that intestine can secrete, digest, and absorb efficiently |
|
After a heavy meal, blood pH increases, especially in veins coming from the stomach. Why?
|
bicarbonate ions pass from parietal cells into the blood
|
|
What component of food would increase the number of chylomicrons in the lacteals?
|
A meal high in fat would increase chlyomicrons because they are fat-protein packages.
|
|
The absorption of which vitamin would be impaired by the removal of the stomach?
|
vitamin B12, this vitamin requires intrinsic factor for absorption which is produced by the parietal cells of the stomach
|
|
Why is it that diarrhea is potentially life-threatening, but constipation is not?
|
the loss of fluid and electrolytes can cause dehydration and even death, constipation doesn't cause such severe problems because the excess waste can eventually be taken care of by the kidneys
|
|
A branch of the portal vein, hepatic artery, and tributary of the bile duct form the
|
portal areas
|
|
The major functions of the large intestine are
|
-reabsorption of water and compaction of feces
-absorption of vitamins liberated by bacterial action -storage of fecal material prior to defacation |
|
Three vitamins generated by bacteria in the colon are
|
vitamin K, biotin, pantothenic acid, vitamin B5
|
|
What are the three primary functions of the large intestine?
|
1-resorption of water and compaction of the intestinal contents into feces
2-absorption of important vitamins liberated by bacterial action 3-storage of fecal material prior to defacation |
|
What two positive feedback loops are involved in the defacation reflex?
|
1-stretch receptors in the rectal walls promote a series of rectal contractions in the colon and rectum, moving feces towards the anus
2- the sacral parasympathetic system innervated by stretch receptors stimulates peristalsis via motor commands distributed by the pelvic nerves |
|
How is the small intestine adapted for the absorption of nutrients?
|
inreased surface area
-walls folded into plicae -villi -microvilli rich supply of blood vessels and lymphatic vessels to transport nutrients that are absorbed |
|
How does a meal that is high in fat affect the level of cholecystokinin (CCK) in the blood?
|
it increases it
|
|
How would the pH of the intestinal contents be affected if the small intestine did not produce secretin?
|
the pH would be lower because the pancreas would have less stimulation to produce and secrete buffers
|
|
The digestion of which nutrient would be most impaired by damage to the exocrine pancreas?
|
lipid digestion, the pancreas is the primary source of lipases, for carbs there would still be enzymes from saliva and small intestine and protein enzymes from stomach and small intestine
|
|
What are the primary functions of the pancreas, liver, and gall bladder in digestion?
|
pancreas- digestive enzymes and buffers
liver and gallbladder- bile for digestion and absorption of lipids liver- metabolic and hematological regulation, bile production, primary organ of blood content regulation |