Midterm 2: Liver, Gallbladder, Pancreas, Spleen

Question 1

pear shaped organ adjacent to inferior-posterior surface of the liver

Answer 1

Gallbladder

Question 2

What is the lumen of the gallbladder lined with?

Answer 2

Simple columnar epithelium

Question 3

main function of the gallbladder

Answer 3

store bile that is produced by the liver

Question 4

What is the flow of bile from the liver to the gallbladder?

Answer 4

hepatic ducts → common hepatic duct → juncture of cystic duct and common bile duct (or just ‘bile duct’) → cystic duct → gallbladder

Question 5

Flow of bile from the liver to the duodenum of the small intestine

Answer 5

hepatic ducts → common hepatic duct → bile duct → hepatopancreatic ampulla → duodenal lumen

Question 6

What kind of secretions does the pancreas have?

Answer 6

Both exocrine and endocrine

Question 7

Describe the exocrine secretions of the pancreas

Answer 7

Secreted directly into the ducts.
Secreted in their inactive form (prohormones = zymogens)
Enzymes secreted are proteases, pancreatic lipase and amylase, and nucleases (RNA/DNA digestion), and HCO3- secretions

Question 8

Where is the spleen located?

Answer 8

upper right quadrant of abdominal cavity

Question 9

Where does the spleen get its arterial blood?

Answer 9

splenic artery, one of the three main branches of the celiac trunk

Question 10

Where does the spleen drain its blood?

Answer 10

hepatic portal system

Question 11

Spleen function

Answer 11

Filters worn out RBC and breaks down heme from the hemoglobin to produce bilirubin. Sends it to the liver through the hepatic portal system vasculature then gets excreted by the body through feces or urine

Question 12

What are the endocrine secreting cells in the islets of Langerhans od the pancreas? What do they secrete?

Answer 12

Alpha cells: glucagon
Beta cells: insulin
Delta cells: somatosatin
Gamma/PP cells: pancreatic polypeptide

Question 13

Describe the alpha cells in the pancreas.

Answer 13

• Endocrine
• Synthesize glucagon which then passes through portal circulation to the liver where its binds to receptors on the hepatocytes that line the sinusoids of the liver lobule; the hepatocytes then convert glycogen to glucose; glucose then is released into circulation that ultimately results in increased blood sugar levels.

Question 14

Describe the beta cells in the pancreas

Answer 14

Endocrine
Synthesize insulin which has an opposing effect on blood sugar levels compared to glucagon; these cells are, by far, the most numerous within the Islets.

Question 15

Describe the delta cells in the pancreas

Answer 15

Somatostatin production which inhibits both synthesis of glucagon and insulin within their respective cells of the Islets.

Question 16

Describe the gamma/pp cells in the pancreas

Answer 16

Inhibits exocrine function via pancreatic polypeptide (PP); rarest of the cell types within the Islets.

Question 17

Where is the liver located?

Answer 17

upper right quadrant of abdominal cavity with portion of left lobe crossing mid-line into the upper left quadrant

Question 18

Lobes of the liver

Answer 18

4 lobes.
Right
Left
Caudate
Quadrate

Question 19

How is the liver suspended in the abdominal cavity?

Answer 19

By 2 peritoneal ligaments.

The falciform ligament attaches the liver to the anterior wall of abdominal cavity and attaches a small portion to diaphragm.

The coronary and triangular ligaments attach liver to the diaphragm

Question 20

What is the the round ligament on the liver?

Answer 20

located at inferior edge of falciform ligament and is remnant of umbilical vein.

Question 21

What enters at the hilum/ portages hepatis on the liver?

Answer 21

Portal vein, hepatic artery, hepatic ducts

Question 22

Flow of venous, arterial, and bile flow in the liver

Answer 22

venous and arterial blood enter the liver while bile flow in the hepatic duct runs countercurrent

Question 23

Describe the lobules of the liver

Answer 23

• Hexagonal-shaped functional unit of the liver with the portal triad located at the corners of the hexagon; the portal triad contains:
  1) vein (a distal branch of the portal vein)
  2) artery (a distal branch of the right and left hepatic artery)
  3) bile duct (a small branch which, when combined with other similar ducts, will eventually form the hepatic ducts)

Question 24

What are the sinusoids of the liver? What are they lined with? Describe

Answer 24

• Vascular channels (discontinuous capillaries) contains venous blood from portal circulation and arterial blood from the hepatic artery,
• Lined mostly with hepatocytes, but also contain phagocytic Kuppfer cells. The sinusoid nearest the periphery of the lobule is the most oxygenated while the center of the lobule contains blood that is more deoxygenated. At the center of the lobule, a central vein collects venous blood and eventually returns it to the inferior vena cava via the hepatic vv.

Question 25

In the endocrine part pancreas, what percent are alpha cells?

Answer 25

20%

Question 26

In the endocrine part pancreas, what percent are beta cells?

Answer 26

70%

Question 27

In the endocrine part pancreas, what percent are delta cells?

Answer 27

5%

Question 28

In the endocrine part pancreas, what percent are gamma/PP cells?

Answer 28

less than 5%

Question 29

What happens when insulin levels increase?

Answer 29

• Insulin binds to receptor (alpha portion)
• The enzyme tyrosine kinase phosphorylates receptors (beta domains) on inner surface of cell
• After a series of other steps, glucose transporter proteins embedded into wall of a vesicle, translocate to plasma membrane

Glucose passively diffuses into cell via a glucose transporter

Question 30

What happens when insulin levels decrease?

Answer 30

the insulin will disassociate from the receptor and the glucose transporters will translocate back into the wall of the cytoplasmic vesicle