Salivary and gastric secretions

Question 1

What is Schirmer’s test?

Answer 1

A test involving filter paper placed inside the eyelids to assess for tear production. Inadequate tear production could suggest Sjogren’s syndrome.

Question 2

Describe the physical and chemical barriers that prevent the gastric mucosa from being damaged by stomach acid

Answer 2

1. Surface mucous glands secrete a viscous mucus layer generating a mucosal barrier
   
   2. Mucin’s basic side chains prevent neutralisation of mucin.
   3. Bicarb is also secreted from surface epithelial cells, which helps to neutralise H+ ions
   4. Tight junctions stop acid from damaging underlying tissue
   5. pH of the mucous layer is about 7, so pepsinogen is not activated

Question 3

This refers to the rapid division of stem cells that occurs after acute damage to the gastric mucosa

Answer 3

Restitution

Question 4

which part of the small intestine has intestinal juices mainly comprised of bicarbonate and mucous?

Answer 4

the duodenum

Question 5

which cells synthesize bile?

Answer 5

hepatocytes

Question 6

What are some of the hormones involved in regulating bile and pancreatic secretions?

Answer 6

Secretin, CCK, and GIP

Question 7

_________ glands are located in the submucosa of the duodenum. They secrete an alkaline fluid containing mucin, which protects the mucosa from the acidic stomach contents entering the duodenum

Answer 7

Brunner’s

Question 8

The bulk of chemical digestion and nutrient absorption occurs mostly in which part of the small intestine?
`

Answer 8

the jejunum

Question 9

In which part of the small intestine does B12 absorption occur?

Answer 9

the ileum

Question 10

What three features of the intestinal mucosa help to increase surface area and aid absorption of nutrients?

Answer 10

Circular folds (plicae circularis), villi, and microvilli

Question 11

___________, or intestinal absorptive cells, are simple columnar epithelial cells that line the inner surface of the small and large intestines. A glycocalyx surface coat contains digestive enzymes.

Answer 11

Enterocytes

Question 12

Which cells secrete CCK?

Answer 12

I cells

Question 13

Which cells secrete secretin?

Answer 13

S cells

Question 14

Which cells secrete gastric inhibitory polypeptide? (GIP)

Answer 14

K cells

Question 15

This hormone stimulates pancreatic and GB secretions

Answer 15

CCK

Question 16

This hormone stimulates pancreatic and biliary bicarbonate secretions

Answer 16

secretin

Question 17

This hormone may inhibit acid secretion (or inhibit the action of the “secretin” family of hormones and/or stimulate insulin release

Answer 17

GIP

Question 18

secretions from the pancreas are regulated by which cranial nerve?

Answer 18

CN X (Vagus)

Question 19

99% of the pancreatic glandular epithelial clusters are responsible for the secretion of

Answer 19

pancreatic juice

Question 20

What are the 4 types of secreting cells within the endocrine pancreatic islets?

Answer 20

Alpha
Beta
Delta
F (or PP) cells

Question 21

Alpha cells secrete

Answer 21

glucagon

Question 22

Beta cells secrete

Answer 22

insulin

Question 23

Delta cells secrete

Answer 23

Somatostatin

Question 24

F cells (or PP cells) secrete

Answer 24

Pancreatic polypeptide

Question 25

Ductular secretions of the pancreas are highest in which components?

Answer 25

sodium and BICARBONATE (bicarb-rich, low enzyme pancreatic juice)

Question 26

Pancreatic acinar secretions are highest in which components?

Answer 26

Sodium and chloride (salt)

acinar secretions are ENZYME RICH

Question 27

The presence of chyme containing fat and protein products in the duodenum triggers the release of which hormone?

Answer 27

CCK

Question 28

What is the trigger for the release of secretin?

Answer 28

H+ ions in highly acidic chyme in the duodenum

Question 29

Where are proteolytic enzymes converted into their active form?

Answer 29

the brush border of the small intestine

Question 30

Which enzyme present in the intestinal brush border acts on trypsinogen to form trypsin?

Answer 30

Enterokinase

Question 31

Which substance cleaves and activates proteolytic enzymes?

Answer 31

Trypsin

Question 32

Where are pro-enzymes (the inactivated version of proteolytic enzymes) produced and secreted from?

Answer 32

exocrine acinar clusters of the pancreas

Question 33

The CFTR channel is stimulated by which hormone (via cAMP)?

Answer 33

secretin

Question 34

What substance acts to emulsify fats for digestion by pancreatic lipase?

Answer 34

Bile salts (or bile)

Question 35

what are the two main roles of bile?

Answer 35

1. emulsifies fats

2. aids with elimination of waste products such as bilirubin, cholesterol, and drugs

Question 36

What type of glands (found only in the duodenum) secrete bicarbonate and mucous?

Answer 36

Brunner’s glands

Question 37

An enzyme found in the small intestinal brush border, _______, converts trypsinogen into the active trypsin

Answer 37

ernterokinase

Question 38

Proteolytic enzymes are produced as inactive precurosors called

Answer 38

zymogens

Question 39

Alpha cells of the pancreas secrete

Answer 39

Glucagon

Question 40

Beta cells of the pancreas secrete

Answer 40

Insulin

Question 41

Delta cells of the pancreas secrete

Answer 41

somatostatin

Question 42

F (aka PP) cells of the pancreas secrete

Answer 42

pancreatic polypeptide