Chapters 24-25 Flashcards
1) What is the general description of the digestive system and does it share organs with other systems??
includes a tube that extends from the mouth to the anus, includes organs that food does not actually enter, shares some structures with the respiratory system
2) Hydrolysis of large biological molecules into smaller ones that can be absorbed by cells is called what?
chemical digestion
3) What makes up the mucosa of the alimentary canal and what does it do?
is composed of three layers: epithelium, lamina propria and the muscularis mucosae which lines the lumen of the alimentary canal
4) During abdominal surgery, immobilization of the patient’s intestines is often desirable. Which of the following types of medications would be most effective at immobilizing the intestines?
an anticholimergic medication
5) What is the peritoneum?
largest serous membrane in the body
6) Where is saliva produced and what does it do?
largely secreted by the parotid, sublinguial and submandibular glands, is rich in amylase, comes primarily from the parotid and submandibular glands, helps moisten food so that it can be swallowed, contains primarily water
7) What muscles are found in the tongue and what are they used for?
contains intrinsic muscles used in speaking and swallowing
8) The remains of a human child are found. There are some deciduous teeth in the jaws, but permanent incisors and 1st molars are clearly present and show some wear. Second molars are barely visible, but show no wear. Based on this evidence, the age of the child at the time of death
can be estimated as older than six years and younger than twelve years
9) A lab group is sent to the cafeteria to do an experiment. The instructions direct each student to obtain a regular saltine cracker and to chew it 25 times before swallowing. The students are to observe and record the initial and final tastes of the cracker. Most students record that the cracker initially tastes salty, but then tastes sweet. Which of the following correctly explains the students’ observations?
the salt on the crackers dissolved rapidly in saliva nad was quickly detected by the taste buds, salivary amylase digested the crackers starch into sugars that could be tasted
10) What is the pharynx?
extends from the internal nares to the esophagus
11) What does the esophagus do?
extends from the inferior end of the pharynx to the stomach, contains skeletal muscle near the pharynx and smooth muscle near the stomach, is lined by a mucous membrane and covered by an adventita
12) What are the functions of the stomach?
Not: serves as a primary absorption site for most nutrients
13) The exit of the stomach, which is sometimes stenosed in infants, is what?
pyloris
14) An individual suffering from hyposecretion by gastric chief cells would have what condition?
inadequate amounts of pepsinogen and gastric lipase
15) What does HCl production depend on?
on the H+/K+ ATPase pumps in the plasma mebrane of parietal cells, is accompanied by increased release of HCO3 into the interstitial fluid, is stiumulated by Ach gastin and histamine
16) Why doesn’t gastric juice digest the stomach?
the stomach is protected by alkaline mucous membrane, the proteolytic enzyme produced by the stomach is secreted in inactive form
17) What is absorbed by the gastric epithelium?
Not: Glucose
18) How does the pancreas function and deliver its juices for digestion?
passes pancreatic juice to the duodenum via the pancreatic duct and hepatopancreatic ampulla
19) What is found in pancreatic juice?
Not: HCL
20) What does the sodium bicarbonate in pancreatic juice do?
elevates the Ph of chyme, which blocks the action of pepsin, creates favorable conditions for the actions of intestinal enzymes
21) What does the liver make?
bile
22) What is the function of the gallbladder?
concentrates and stores bile
23) What is found in bile?
contains water, bile salts, bile pigments, ile acids, cholesterol, lecithen and ions
24) What do hepatocytes do?
Not: convert bileverdin to hemoglobin
25) What homeostatic disturbances might result from liver failure?
decreased ability to maintain normal blood glucose levels
26) What makes up the small intestine and what does it do?
major sight of digestion and absorption, consists of the duodenum, jejunum and ilium, has villi, and microvilli that increase its surface area for absoprtion, contains circualr folds that increase surface area and absorption.
27) Which substrates are digested by which brush border enzymes?
carbohydrate: adextrinase, maltase, lactase, sucrase,
Protein: aminopeptidase, dipeptidase
Nucleotide: nucelosidases, phosphatases
28) Which enzyme digests triglycerides?
Not: pancreatic amylase
29) What substances are absorbed across the epithelium of the small intestine?
Not: tryglicerides
30) Which substances are absorbed via some form of active transport?
Not: Fatty acids
31) What are the functions of the large intestine?
completion of absorption, productino of certain vitamins, formation of feces, elimination of feces.
32) What is the order of the structures in which chyme and, ultimately, feces pass through?
ileocecal valve, cecum, asending colon, transverse colon, desceinding colon, sigmoid colon, rectum, anus
33) What do the bacteria in the large intestine do?
ferment any carbohydtates left in chyme and release H2, CO2 and CH4 gases, convert any amino acids left in chyme into simpler substances, decomposes biliruben to simpler pigments such as stereobilin, synthesize some B vitamins and Vitamin K.
34) What forms the primitive gut in the embryo?
epithelium of most of the digestive tract
35) What are some of the expected age-related changes in the digestive system?
decreased secretory mechanusms, decreased smooth muscle tone, decreased motility
36) What is the process that releases fecal material through the anus?
defecation
37) What is the process when digested molecules enter into epithelial cells lining the intestinal lumen?
absorption
38) What is the process called that moves materials through GI tract, mostly via peristalsis?
propulsion
39) What structure contains adipose tissue and lymph nodes; can move to sequester an inflamed appendix?
greater amentum
40) What structure aids mesentery in anchoring intestines while allowing them some mobility; contains lymphatic and blood vessels?
mesocolon