Digestive system - Part 2 Flashcards
What are the absorptive cells of the small intestine?
Enterocytes
What do enteroendocrine cells do?
Secrete hormones
Describe intestinal crypts/glands.
Epithelial cells secrete intestinal juices
Cells regenerate here
What are the different cells of the intestinal wall?
Absorptive cells - enterocytes
Goblet cells
Enteroendocrine cells
Intestinal crypts/glands
Enterocytes are what tissue type?
Simple columnar epithelial cells
In each villus, there are _______, ______, and ______ vessels
arteries, veins and lymph vessels
There are lots of mitochondria in the small intestine. Why?
absorption is a very energy-dependent process
What are the main functions of the large intestine?
Absorb water and electrolytes
There is also _________ digestion in the large intestine.
bacterial
Mass __________ movements move feces toward the rectum.
peristaltic
Describe why people get gas when lactose intolerant.
Lactase is activated in the duodenum, deficient in these people.
Lactose not absorbed through the SI like normal.
In this case, digested by bacteria which produce gas.
What is the teniae coli?
thickening of longitudinal muscularis
What are haustra?
Puckering created by teniae coli; “sacs”
What are Epiploic appendages?
Fat-filled pouches of visceral peritoneum
What is the cecum?
(Blind pouch)
Beginning of large intestine
What is the vermiform appendix?
What does it contain/do?
Contains lymphoid tissue which neutralizes pathogens.
What is the colon divided into?
Ascending, descending, transverse
Rectum.
What does it descend into?
What is well-developed in it?
Descends along the inferior half of the sacrum.
Well-developed longitudinal layer to generate strong contractions for defecation.
What is the anal canal?
What tissue type is here?
Last subdivision of the large intestine.
Stratified squamous epithelium
What comes off the cecum?
Appendix
The rectum has a well-developed _________ _________.
longitudinal muscularis
________ valve controls undigestible residue from the ileum.
Ileocecal
Describe how the ileocecal valve works.
As the residue is leached into the LI, the cecum fills up and pulls on the ascending colon, closing off this valve, peristalsis moves feces towards anal canal.
Prevents it from going back to ileum
Where is the right colic flexure?
What is located there?
Ascending colon
Liver there
What is on the left colic flexure?
spleen
What is the danger with the appendix bursting.
Bacteria and shit leak into the body cavity, peritoneal cavity, bacteria carried by bloodstream causing sepsis.
Lots of water absorbed means ________, lots of water in the LI means _________.
constipation
diarrhea
Microscopic anatomy of the large intestine:
______ are absent
Contains numerous ______ cells
Intestinal crypts are lined with _______ (tissue type) and have absorptive cells called _________
The epithelium changes at the anal canal, becoming _____ _______.
Villi goblet simple columnar colonocytes stratified squamous
The liver is the largest _____ in the body.
It produces ______ - digestive function
It performs many metabolic function:
- Processing _____
- Stores _______
- Detoxifies ______ and ______
Located just inferior to the ______ on the _____ side.
Humans have ___ lobes
The hepatic portal system is located on the _______ side.
gland bile fats vitamins poisons and drugs diaphragm 4 posterior
What are the functional cells of the liver?
Hepatocytes
The portal triad of the liver is composed of what?
Bile duct tributary
Branch of hepatic portal vein
Branch of hepatic artery
What are kupffer cells?
Located in the liver,
destroy bacteria
The rough ER of the liver manufactures what?
The smooth ER of the liver produces what? What other function does the smooth ER do?
Peroxisomes of the liver detoxify ______.
Glycosomes of the liver store _______.
The liver has a great capacity for _________.
_________ provide energy for all of the functions.
Rough ER - blood proteins Smooth ER - produce bile and detoxifies poisons Peroxisomes - detoxify alcohol Glycosomes store sugar Great capacity for regeneration Mitochondria provide energy
What is cirrhosis of the liver?
Liver is shrunken down
What colour is the liver? Why?
Red, highly vascularized
At each corner of a lobule is a group of three vessels. These are?
Portal arteriole, portal veinule, bile duct
What do the portal arterioles do?
Carry oxygen and nutrients to tissue
Where to hepatic veinules branch off of?
Branches off hepatic portal vein
What does the hepatic portal system do?
Takes nutrients from digestive organs and shuttles them to the liver for processing.
What are bile canaliculi?
Allow bile to be made and leached out
What is the capillary bed in the liver?
Sinusoids
The lobule is drained by the _____ _____ which drains to the _______ _____ then to the ____ ____ _____ which unloads blood into the RA?
central vein
hepatic vein
IVC
Final venous drainage of the hepatic portal system is the _______ vein.
central
All central veins converge onto _______ veins.
hepatic
Where is the first capillary bed of the hepatic portal system located?
Digestive organs
Describe the hepatic portal vein.
Brings deoxygenated nutrient rich blood from stomach, spleen and intestines
Describe the path of blood through the hepatic portal system starting at the hepatic artery and portal vein.
1 - Oxygenated blood from the hepatic artery
1 - Nutrient rich, deoxygenated blood from hepatic portal vein
2 - Liver sinusoids
3 - Central vein
4 - Hepatic vein
5 - IVC
6 - RA
Describe the action of the gallbladder.
Stores and concentrates bile.
Expels bile into duodenum.
What does bile do?
Emulsifies fats/cholesterol
Describe gallstones.
How are they caused.
How can they cause pain.
How are they treated?
Too much fat and too little bile salts, leading to crystallization in the gallbladder.
Gallstones can plug cystic ducts and cause pain when the gallbladder contracts.
Treated via drugs to dissolve stones or vapourizing them with a laser, or removal of the gallbladder.
What does a fatty chyme signal?
Feedsback to cause release of bile.
What is a special structure in the mucosa of the gallbladder?
What does it do?
ruggae - allow for expansion to receive bile
The cystic duct of the gallbladder meets up with what?
common hepatic duct
The pancreas has two functions. These are?
Exocrine
Endocrine
What are acinar cells?
Make, store and secrete pancreatic enzymes
Where are pancreatic enzymes active?
duodenum
What is the endocrine function of the pancreas?
Produces insulin and glucagon - helps regulate blood sugar
Acinar cells make ______ granules, allow secretion of ________ enzymes.
zymogen
digestive
Where does the head of the pancreas lie?
In the C-shaped curve of the duodenum
The main pancreatic duct joins the common bile duct to release its contents into the duodenum at the ___________ _________
hepatopancreatic ampulla
