L30. Accessory gland

Question 1

Describe the digestive glands

Answer 1

1. evaginations of the endodermal tube near the small intestine
2. all 3 glands empty their contents through ducts into the small intestine ( with connections maintained)

Question 2

What are the 3 digestive glands attached to the small intestine

Answer 2

1. pancreas
2. liver
3. gall bladder

Question 3

Describe the pancreas

Answer 3

1. has dual function: both endocrine and exocrine function
2. endocrine: ductless- islets secrete insulin and glucagon
3. exocrine: with ducts- acini which secrete digestive enzymes and bicarbonates

Question 4

Describe the liver

Answer 4

1. multiple functions occur within the single cell -hepatocytes
2. materials that are delivered to and drained from the hepatocytes come from the hepatic portal triad
3. has both an exocrine and endocrine function

Question 5

Describe the gall bladder

Answer 5

stores and secretes the exocrine product (bile) produced from the liver

Question 6

When does the accessory organs from the endodermal tube form

Answer 6

6th week of gastrulation

Question 7

Describe how the 3 digestive glands eventually form during gastrulation

Answer 7

1. glands form as buds out from the endodermal tube
2. there is rotation of the glands from the ventral side to the dorsal side
3. there would be fusion between teh ventral and dorsal pancreas
4. contents of the 3 glands will exit through ducts through a point known as the sphincter of oddi

Question 8

What is the sphincter of oddi

Answer 8

It is the point where exocrine ducts of the pancreas liver and gall bladder empty their secretions to the small intestine

Question 9

What forms the sphincter of oddi

Answer 9

fusion between the primary pancreatic duct and the common bile duct

Question 10

How many pancreatic ducts are there?

Answer 10

2 , the accessory pancreatic duct and the primary pancreatic duct

Question 11

In the pancreas which cells ar chromophobic and which are chromophillic

Answer 11

The islets cells (endocrine secretion) are chromophobic

the acini cells (exocrine secretion) are chromphillic

Question 12

What are alpha cells

Answer 12

endocrine cells in the islets that secrete glucagon that increases blood glucose level

Question 13

What are beta cells

Answer 13

endocrine cells in the islets that secrete insulin that decrease blood glucose level

Question 14

What class of hormones are insulin and glucagon

Answer 14

peptide hormones

Question 15

What happens in type 2 diabetes

Answer 15

beta cells secrete loads of insulin but cell surface receptors are not as sensitive to insulin or there is some probelm with the signaling pathway in recipient cells

Question 16

What are the 2 cell types involved in exocrine secretion in the pancrease

Answer 16

1. acinar cells
2. centroacinar cells
   * * involved in apical secretion

Question 17

What is the function of centroacinar cells

Answer 17

secrete bicarbonate ions (make the alkali fluid)

Question 18

Where do lumens in the pancreas lead to

Answer 18

1. lead to lobular ducts
2. which drain to the pancreatic duct
3. access to the sphincter of oddi

Question 19

What do acinar cells secrete

Answer 19

zymogen -trypsinogen

Question 20

What is the function of CCK

Answer 20

causes the apical and lumenal secretion of the products from acinar and centroacinar ( zymogen + bicarbonate ) into the small intestine

Question 21

Where is CCK produced

Answer 21

by the DNES cells in the small intestine

Question 22

What happens to the pancreas when there is a problem with the CFTR

Answer 22

there will be thickened/blocked pancreatic duct as the serous/bicarbonate secretions are thickened.

Question 23

What are the functions of the liver

Answer 23

1. endocrine secretion ( plasma protein production)
2. exocrine secretion ( bile production)
3. lipid and glucose storage (glycogen production)
4. detoxification ( alcohol detox)
   * all done within 1 cell type: hepatocyte

Question 24

Describe the blood supply in the liver

Answer 24

has a dual blood supply into the liver

1. oxygenated blood obtained from hepatic artery: blood from the arteriole to liver
2. hepatic portal vein: drains all the GI fluid ( including nutrients) this vein also drains from the spleen which is where billirubin (from RBC) comes from
   - has big open capillaries (venous sinosoids) : so there are tons of transport

Bile ducts out of the liver
3. drains liver of the exocrine product

Question 25

What is billirubin

Answer 25

stuff from the RBC to make bile salts

Question 26

What is the hepatic portal triad

Answer 26

consists of the 2 blood vessels entering the liver (hepatic artery and hepatic portal vein) and the exocrine duct ( bile duct) leaving the liver

Question 27

What is a portal vein

Answer 27

capillary->vein->capillary

1. drains all of the GI tract to get nutrients and drains the spleen to get the broken down heme

Question 28

How does blood get out of the liver

Answer 28

(blood leaves liver through the hepatic veins)

1. blood enters from the hepatic portal vein and hepatic artery and flow through the venous sinosoids.
2. the blood from the 2 sources gets mixed and modified by the hepatocytes
3. central veins in the liver lobules collect blood from the hepatic sinosoids
4. drain into the inferior vena cava

Question 29

What are the endocrine products of the liver

Answer 29

plasma proteins and lipoproteins

Question 30

What are the exocrine products of the liver

Answer 30

bile salts,cholesterol,billirubulin

Question 31

What are the 2 dual domains of hepatocyte secretion

Answer 31

1. sinosoidal domain ( basal)

2. billary doman (apical)

Question 32

Describe the sinosoidal domain of the hepatocyte

Answer 32

empties into the sub-sinosoidal ( space of disse)

endocrine

Question 33

Describe the billary domain of the hepatocyte

Answer 33

exocrine
has tight junctions
empties into bile cannaliculi
secretes into the bile duct