Histology > Exam3Lec3Digestive3 > Flashcards

Exam3Lec3Digestive3 Flashcards

(49 cards)

Study These 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?

Study These Flashcards
A

alcoholism, certain viral infections, autoimmune disease

21
Q

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

Study These Flashcards
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?

Study These Flashcards
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 = ____ + ____ + ____

Study These Flashcards
A

portal triad = portal vein +hepatic artery + bile duct

24
Q

What is the order of the biliary tree?

Study These Flashcards
A

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

25
What is the canaliculi of the biliary tree?
hepatocytes w/ tight junctions
26
What is the common bile duct of the biliary tree?
Common bile duct = hepatic duct (from liver) + cystic duct (from gallbladder)
27
What type of epithelium lines the ductule and duct of the biliary tree?
Ductule = simple cuboidal epithelium Duct = simple columnar epithelium + microvilli
28
Where and when is bile eventually secreted?
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
What type of epithelium lines the gallbladder?
simple columnar w/ microvilli
30
What does the mucosa of the gallbladder form and lack?
Forms folds + lateral plicae for increased surface area Lacks muscularis mucosa ## Footnote mucosa = epithelium + lamina propria (loose CT) + muscularis mucosae
31
What is the fxn of the gallbladder?
stores + concentrates bile from the liver Also absorbs water + electrolytes
32
What is bile secretion regulated by?
CCK (cholecystokinin)
33
How is bile secretion regulated by CCK (cholecystokini)?
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
What do gallstones in the cystic duct and gallstones in the bile duct lead to?
* Gallstones in the *cystic duct*: this blockage leads to cholecystitis * Gallstones in the *bile duct* : this blockage leads to obstructive jaundice
35
What is the *exocrine* fxn of the pancreas?
Exocrine (serous) glands secrete digestive enzymes into duodenum
36
What is the exocrine fxn of the pancreas regulated by?
Regulated by **Secretin + CCK** via enteroendocrine cells: * Secretin stimulates HCO3- secretion * Cholecystokinin (CCK) stimulates zymogen secretion ## Footnote Secretes HCO3- & Na+ & H2O into the duodenum Secretes digestive zymogens into the duodenum
37
What is the organization of the exocrine gland of the pancreas?
1. Acinus 2. Intercalated duct 3. Intralobular duct 4. Interlobular duct 5. Main duct ## Footnote NOTE: there are NO striated ducts in the pancreas, only the salivary glands
38
What is the fxn of the acinus in the exocrine gland of the pancreas?
secrete fluid + zymogens (lipase, trypsin, chymotrypsin, amylase)
39
The pancreatic lobules consist largely of what?
exocrine acini and their intralobular duct system
40
Duodenum: * What is the absorptive cell? * What does it contain? * What does entrokinase activate?
* Absorptive cell: Enterocyte with microvilli Contains:enterokinase within the cell membrane of microvilli. * Entokinase activates pancreatic proenzymes (zymogens)
41
enterokinase from microvilli activates what?
pancreatic proenzymes (zymogens)
42
What is the fxn of the intercalated duct and note the type of epithelium it contains
simple squam. centroacinar cells secrete HCO3- & Na+
43
What type of epithelium makes up the intralobular duct and the interlobular duct?
* Intralobular duct = simple cuboidal/columnar (NO striations) * Interlobular duct = simple columnar
44
What does exocrine liver and endocrine liver secrete into?
Exo: into the bile canaliculi Endo: into the sinusoids
45
What is the fxn of the main duct of the pancreatic exocrine gland?
* secretes fluid + digestive enzymes into the duodenum * Joins the common bile duct before entering duodenum
46
What is cystic fibrosis? What does it effect?
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
What is the fxn of the *endocrine gland* of the pancreas?
Regulates blood glucose (sugar) levels
48
What is the fxn of islets of Langerhans cells?
secrete hormones into the blood
49
What hormones are secreted by Islets of Langerhans
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
flashcards
Decks in class (39)
# Cards
Brainscape helps you reach your goals faster, through stronger study habits.
© 2026 Bold Learning Solutions. Terms and Conditions