Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Histology > Exam3Lec3Digestive3 > Flashcards

Exam3Lec3Digestive3 Flashcards

1
Q

What is the largest gland in the body?

A

Liver

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the hepatic lobule made up of?

A

cells, CT, blood vessels, sinuses + biliary tree

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the structures of the hepatic lobule?

A
  1. Classic Lobule
  2. Portal Lobule
  3. Liver Acinus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Classic lobule
1. Shape
2. Central vein lxn
3. Portal triad lxn

A
  1. Shape: hexagonal
  2. Central vein lxn: at the center
  3. Portal triad lxn: at each point of the hexagon
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Portal lobule
1. Shape
2. Central vein lxn
3. Portal triad lxn

A
  1. Shape: triangular
  2. Central vein lxn: at each point of the triangle
  3. Portal triad lxn: at the center
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Liver Acinus
1. Shape
2. Central vein lxn
3. Portal triad lxn

A
  1. Shape: oval (elliptical)
  2. Central vein lxn: horizontal ends
  3. Portal triad lxn: vertical ends
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

List the location and fxn of each zone of the liver acinus
1. Zone 1
2. Zone 2
3. Zone 3

A
  1. Zone 1: = closest to center (axis) -> receive nutrients + toxins first
  2. Zone 2: Zone 2 = middle ->receive nutrients + toxins 2nd
  3. Zone 3: furthest from center (axis)  receive nutrients + toxins last
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Toxins mainly affects which zone of the liver acinus? Oxygen depletion mainly affects which zone of the liver acinus?

A

toxins mainly affect zone 1; oxygen depletion mainly affects zone 3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the 3 types of liver cells?

A

Hepatocytes, Hepatic Stellate Cells (Ito cells), Kupffer cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are hepatocytes?

A

large polygonal cells w/ microvilli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the endocrine and exocrine fxn of hepatocytes?
What is the exocrine fxn regulated by?
What do the organelles do?

A

Endocrine fxn = make + secrete proteins/lipoproteins into the blood
Exocrine fxn = make + secrete bile into bile ducts and gallbladder
Exocrine fxn regulated by CCK
Organelles degrade toxins (sER) + store lipofuscin pigment (lysosomes)

Granules store glycogen + lipids  stain acidophilic (pink)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Hepatic Stellate Cells = Ito Cells
1. Lxn
2. Fxn

A
  1. Lxn:Space of Disse
  2. Fxn: store fat + vitamin A & produce type I collagen fibers
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Kupffer Cells
1. Lxn
2. Fxn

A
  1. Lxn: inside sinusoids (capillaries)
  2. Fxn: breakdown of damaged RBCs  forms bilirubin (pigment)
    Can act as macrophages (phagocytic cells) in the sinusoids
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the space of disse?

A

The space b/n the hepatocytes & the endothelial cells of the sinusoid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What structures are extended/secreted into the space of disse?

A
  • Microvilli of hepatocytes extend into this space for absorption
  • Processes of Kupffer cells extend into this space + act as macrophages
  • Ito cells secrete type I collagen fibers into this space
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the CT of the liver comprised of?

A
  1. Glisson capsule (dense CT)
  2. Fibroblasts + type I collagen= around the portal triads
  3. reticular (type III collagen)= perisinusoidal space and around the central vein
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What can occur if there is damage to hepatocytes? What does each liver cell do?

A

causes them to release cytokines to recruit cells to the area

Kupffer cells can act as macrophages to breakdown damaged cellular material
Ito cells become activated ->transform into myofibroblasts -> produce type I collagen fibers into the space of Disse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

An increase in fibrosis around the portal vein ____ blood flow, which leads to ____ blood pressure. This can lead to ____

A

An increase in fibrosis around the portal vein decreases blood flow, which **increases **blood pressure. This can lead to portal HTN.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is cirrhosis?
What is it caused by?
* Can hepatocytes regenerate?
* death of hepatocytes leads to what?

A
  • Progressive hepatocyte destruction leads to the destruction of normal liver unit structure
    Causes: alcohol toxicity, some forms of viral infection, and autoimmune liver disease.
  • Hepatocytes can regenerate…but NOT their portal system connections
  • Increase in fibrocollagenous tissue (type I collagen) leads to formation of “scar tissue”

chronic liver damage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are 3 causes of cirrhosis?

A

alcoholism, certain viral infections, autoimmune disease

21
Q

What makes up the vascular system of the liver (5)?

A
  1. Portal vein
  2. Hepatic vein
  3. Interlobular vessels in triads
  4. Sinusoids
  5. Central vein

portal vein → hepatic vein → interlobular vessels → sinuses → central vein

22
Q

What are the blood vessels of the liver unit and list the fxn for each?

A
  1. Portal vein: brings deoxygenated blood from the intestines, pancreas + spleen to the liver = 75% of blood
  2. Hepatic artery: brings oxygenated blood from the heart to the liver = 25% of blood
  3. Interlobular vessels: branch off from the hepatic artery and deliver blood to the sinusoids
  4. Sinusoids: (=discontinuous capillaries) deliver blood to the central vein
  5. Central vein: travels alone in the center of the liver unit (i.e., lobule)

Central vein: In the center of the lobule = not in triad

23
Q

Portal triad = ____ + ____ + ____

A

portal triad = portal vein +hepatic artery + bile duct

24
Q

What is the order of the biliary tree?

A

Bile Canaliculi ->Bile Ductule (interlobular ducts = in portal triad) -> Common Bile Duct

25
Q

What is the canaliculi of the biliary tree?

A

hepatocytes w/ tight junctions

26
Q

What is the common bile duct of the biliary tree?

A

Common bile duct = hepatic duct (from liver) + cystic duct (from gallbladder)

27
Q

What type of epithelium lines the ductule and duct of the biliary tree?

A

Ductule = simple cuboidal epithelium
Duct = simple columnar epithelium + microvilli

28
Q

Where and when is bile eventually secreted?

A

Bile is eventually secreted into the duodenum of the small intestine
After hormonal cholecystokinin – CCK stimulation (from enteroendocrine cells in small intestine) in response to the presence of fat in the duodenum

29
Q

What type of epithelium lines the gallbladder?

A

simple columnar w/ microvilli

30
Q

What does the mucosa of the gallbladder form and lack?

A

Forms folds + lateral plicae for increased surface area
Lacks muscularis mucosa

mucosa = epithelium + lamina propria (loose CT) + muscularis mucosae

31
Q

What is the fxn of the gallbladder?

A

stores + concentrates bile from the liver
Also absorbs water + electrolytes

32
Q

What is bile secretion regulated by?

A

CCK (cholecystokinin)

33
Q

How is bile secretion regulated by CCK (cholecystokini)?

A
  1. Fat in the duodenum stimulates enteroendocrine cells
  2. Enteroendocrine cells secrete CCK into the blood
  3. Activation of bile secretion from gallbladder -> into duodenum
34
Q

What do gallstones in the cystic duct and gallstones in the bile duct lead to?

A
  • Gallstones in the cystic duct: this blockage leads to cholecystitis
  • Gallstones in the bile duct : this blockage leads to obstructive jaundice
35
Q

What is the exocrine fxn of the pancreas?

A

Exocrine (serous) glands secrete digestive enzymes into duodenum

36
Q

What is the exocrine fxn of the pancreas regulated by?

A

Regulated by Secretin + CCK via enteroendocrine cells:
* Secretin stimulates HCO3- secretion
* Cholecystokinin (CCK) stimulates zymogen secretion

Secretes HCO3- & Na+ & H2O into the duodenum
Secretes digestive zymogens into the duodenum

37
Q

What is the organization of the exocrine gland of the pancreas?

A
  1. Acinus
  2. Intercalated duct
  3. Intralobular duct
  4. Interlobular duct
  5. Main duct

NOTE: there are NO striated ducts in the pancreas, only the salivary glands

38
Q

What is the fxn of the acinus in the exocrine gland of the pancreas?

A

secrete fluid + zymogens (lipase, trypsin, chymotrypsin, amylase)

39
Q

The pancreatic lobules consist largely of what?

A

exocrine acini and their intralobular duct system

40
Q

Duodenum:
* What is the absorptive cell?
* What does it contain?
* What does entrokinase activate?

A
  • Absorptive cell: Enterocyte with microvilli
    Contains:enterokinase within the cell membrane of microvilli.
  • Entokinase activates pancreatic proenzymes (zymogens)
41
Q

enterokinase from microvilli activates what?

A

pancreatic proenzymes (zymogens)

42
Q

What is the fxn of the intercalated duct and note the type of epithelium it contains

A

simple squam. centroacinar cells secrete HCO3- & Na+

43
Q

What type of epithelium makes up the intralobular duct and the interlobular duct?

A
  • Intralobular duct = simple cuboidal/columnar (NO striations)
  • Interlobular duct = simple columnar
44
Q

What does exocrine liver and endocrine liver secrete into?

A

Exo: into the bile canaliculi
Endo: into the sinusoids

45
Q

What is the fxn of the main duct of the pancreatic exocrine gland?

A
  • secretes fluid + digestive enzymes into the duodenum
  • Joins the common bile duct before entering duodenum
46
Q

What is cystic fibrosis?
What does it effect?

A

Decreased Cl- secretion + Na+ absorption -> thick mucous in pancreatic ducts
effects exocrine glands of pancreas: The total loss of pancreatic exocrine secretion impairs protein and fat absorption (exocrine pancreatic insufficiency)

effects exocrine glands of pancreas

47
Q

What is the fxn of the endocrine gland of the pancreas?

A

Regulates blood glucose (sugar) levels

48
Q

What is the fxn of islets of Langerhans cells?

A

secrete hormones into the blood

49
Q

What hormones are secreted by Islets of Langerhans

A
  1. B cells: secrete insulin & decreases blood glucose
  2. A cells: secrete glucagon & increases blood glucose
  3. D cells: secrete somatostatin & inhibit A cells
  4. F cells: secrete pancreatic polypeptide

Histology (39 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions