SI and Pancreas (midterm) Flashcards by Julia Gumirov

The ___________ is more dense CT than the areolar CT in the mucosa

submucosa

How well did you know this?

Not at all

Perfectly

What cells are found in the intestinal glands?

1) absorptive cells
2) goblet cells
3) enteroendocrine cells
4) paneth cells

How well did you know this?

Not at all

Perfectly

What is the function of absorptive cells inside of intestinal glands?

digest and absorb nutrients

How well did you know this?

Not at all

Perfectly

What is the function of goblet cells?

test q

secretes mucus

How well did you know this?

Not at all

Perfectly

What cells secrete hormones like secretin, CCK, and GIP?

enteroendocrine cells

How well did you know this?

Not at all

Perfectly

What is the function of paneth cells?

test q

secretes lysozyme and is capable of phagocytosis to kill bacteria

How well did you know this?

Not at all

Perfectly

Simple columnar cells are found in the mucosal layer of the SI and contains crypts of Lieberkuhn (deep to surface) which secretes ___________ and makes brush border enzymes

intestinal juice (note: this is slightly alkaline (7.6) whereas gastric juice is very acidic)

How well did you know this?

Not at all

Perfectly

The submucosal layer of the SI has duodenal Brunner’s glands that secrete…

alkaline mucus to continue to raise pH of chyme

How well did you know this?

Not at all

Perfectly

Intestinal juice provides a vehicle for absorption of substances from _______ as they come in contact with the villi. Some digestion will continue to occur in the lumen of the SI, especially until pH is neutralized

chyme

How well did you know this?

Not at all

Perfectly

Brush border enzymes break down compounds on the surfaces of their microvilli. Peptidases like ______________________ attach remaining peptide bonds and nucleosideases and phosphatases continue to breakdown DNA and RNA

aminopeptidases or dipeptidases

How well did you know this?

Not at all

Perfectly

Sucrose needs to be converted to what to be digested/absorbed?

glucose or fructose

How well did you know this?

Not at all

Perfectly

Which hormone is secreted in the G cells of the antrum, duodenum, and jejunum, and stimulates gastric acid secretion and mucosal growth in the stomach?

test q

gastrin

How well did you know this?

Not at all

Perfectly

Which hormone is secreted in the I cells of the SI and stimulates:
-pancreatic enzyme secretion
-pancreatic bicarbonate secretion
-gallbladder contraction
-growth of exocrine pancreas
(basically stimulates pancreas to release more exocrine cells)

and inhibits gastric emptying?

test q

CCK

How well did you know this?

Not at all

Perfectly

Which hormone is secreted in the S cells of the SI and stimulates:
-pepsin secretion
-pancreatic bicarbonate secretion
-biliary bicarbonate secretion
-growth of exocrine pancreas

and inhibits gastric acid secretion?

test q

secretin

How well did you know this?

Not at all

Perfectly

Which hormone is secreted in the K cells of the duodenum and jejunum and stimulates insulin release (carbs stimulate insulin release) while inhibiting gastric acid secretion?

test q

gastric inhibitory peptide (GIP)

How well did you know this?

Not at all

Perfectly

What are the 3 parts of the pancreas?

head, body, and tail

How well did you know this?

Not at all

Perfectly

The head of the pancreas is close to the curve in C-shaped ________

duodenum

How well did you know this?

Not at all

Perfectly

The pancreas is connected to the duodenum via the main duct (duct of wirsung) and accessory duct (duct of santorini). The main duct joins the common bile duct from the liver and forms the ________________ duct. The hepatopancreatic sphincter (sphincter of oddi) on the hepatopancreatic ampulla (ampulla of vater) controls secretions (its close to the pyloric sphincter)

note: the location of pancreatic secretion release is relative to chyme released into duodenum

hepatopancreatic

How well did you know this?

Not at all

Perfectly

The pancreatic acini are dark clusters that take up 99% of the gland and produce _____________________________. The islets of langerhans are 1% of the gland and are pale staining cells that produce many hormones

bicarbonate rich pancreatic juice

How well did you know this?

Not at all

Perfectly

The islets of langerhans have alpha cells that produce what hormone? What is the function of this hormone?

glucagon
-raises the conc. of glucose in the bloodstream
-synthesis of glucagon is stimulated during fasting and is decreased during fed state

How well did you know this?

Not at all

Perfectly

The islets of langerhans have beta cells that produce what hormones? What is the function of these hormones?

insulin
-promotes the absorption of glucose from the bloodstream
-synthesis of insulin is stimulated by IV glucose or feeding and is decreased by fasting
-insulin targets the liver, skeletal muscle and adipose tissue to store excess glucose

amylin
-slows gastric emptying and promotes satiety (feeling of fullness)

How well did you know this?

Not at all

Perfectly

What cells are most common in the islets of langerhans?

beta cells are 70% of the cells there

How well did you know this?

Not at all

Perfectly

The islets of langerhans have epsilon cells that produce what hormone? What is the function of this hormone?

the hunger hormone
-secreted when stomach is empty, and stops secretions once the stomach starts stretching from food
-secreted from adipocytes and works in the hypothalamus

How well did you know this?

Not at all

Perfectly

Pancreatic juice is generated in response to ________ from the duodenum and jejunum

secretin

How well did you know this?

Not at all

Perfectly

What does pancreatic juice contain and what does it do?

water, enzymes, and sodium bicarbonate it fixes the pH of chyme exiting the stomach

What are the 5 types of enzymes in pancreatic juice?

1) pancreatic amylase 2) pancreatic lipase 3) trypsinogen 4) serine proteases 5) ribonuclease and deoxyribonuclease

Pancreatic ________ breaks down starch into glucose

amylase

Pancreatic ________ uses hydrolysis to break apart fats to MGs and free FAs

lipase

Trypsinogen is a zymogen activated by _______________ (a brush border enzyme)- ________ is the major protease test q

enteropeptidase (initial enzyme that turns on whole cascade of pancreatic digestive enzyme release) trypsin

All serine proteases are activated by.... test q

trypsin trypsin is a huge activator!!!!

What are the 3 types of serine proteases?

1) chymotrypsinogen> chymotrypsin 2) procarboxypeptidase> carboxypeptidase 3) proelastase> elastase

Elastase is a serine protease that is specialized to break down....

elastin proteins

Which hormone combines with trypsin and is produced inside the pancreas? This hormone prevents self-digestion prior to secretion

trypsin inhibitor

Ribonuclease and deoxyribonuclease digest _____________

nucleic acids

Pancreatic juice secretion is high in bicarbonate, which ________ pH

increases (becomes more alkaline)

Acidic chyme arriving in the SI stimulates release of _________, which stimulates increased bicarbonate release in pancreatic juice

secretin

FAs and sugar in chyme causes increased insulin release with what hormone?

gastric inhibitory peptide (GIP)

Fats and proteins cause release of ____, which inhibits gastric emptying. This hormone increases gastric acid secretion and digestive enzymes release into pancreatic juice, which drives contraction of gallbladder

CCK

what is pancreatitis? What are the causes?

inflammation of the pancreas -caused by gallstones, mumps, corticosteroids, trauma

What is acute pancreatitis most commonly associated with?

heavy alcohol intake or biliary tract obstruction (severity depends on activation level of trypsinogen and other proteolytic enzymes- if they are activated, the patient starts to digest themselves and this can be fatal)

Lingual lipase is more active in the __________ than the mouth

stomach

Absorption in the SI is the passage of the end products of digestion from the GI tract into...

blood or lymph

Monosaccharides are remnants of carb digestion and are absorbed into epithelial cells. Glucose and galactose go through a ________________, which is active transport. Fructose undergoes facilitated diffusion. Then they move out of epithelial cell into blood capillaries in villus through facilitated diffusion

sodium symporter (Na+/K+ pump)

What is the difference between primary and secondary active transport?

primary active transport generated energy directly there, while secondary got energy from elsewhere

AAs and dipeptides absorb into epithelium via secondary active transport with either Na+ or H+ ions (symporters). They are then transported out of epithelial cell into blood capillaries in the villus through_______________, but nothing greater than a tripeptide can get through. From the villus, it is transported to the liver via the hepatic portal vein test q

simple diffusion note: AAs go with Na+, di/tripeptides go with H+ into cell!!!!

Lipids are absorbed as small FAs and enter the epithelial cells and exit by _____________. Larger lipids exist only within micelles (bile salts coating) enter by simple diffusion (leaving bile salts behind in gut). Fat soluble vitamins enter with lipids also within micelles

simple diffusion

When lipids are being absorbed into epithelial cells, the fats are rebuilt and coated with lipoproteins to form _____________, which will leave the intestinal cells by _____________ into a lacteal which will travel to thoracic duct/lymphatic system to reach veins near the heart and be removed from the blood by the liver and adipose tissue test q

chylomicrons, exocytosis

Many of the electrolytes absorbed by the SI come from GI secretions and some are a part of digested foods and liquids. Sodium and potassium are transported through Na+/K+ pump which is an active transporter. _________________ can passively flow through. _____________________ ions have to go through active transport. test q

chloride, iodine, and nitrate iron, magnesium and phosphate

Intestinal calcium absorption requires what? test q

activated vit D and parathyroid hormone

What vitamins are absorbed with ingested dietary lipids and travel in micelles which are absorbed by simple diffusion?

fat soluble vitamins- vit K,A,D,E

What vitamins can be absorbed through simple diffusion?

water soluble vitamins- vit B and C

Which vitamin is absorbed with intrinsic factor (which comes from parietal cells of the stomach) before it is transported into the cells via receptor mediated endocytosis? test q

vit B12

Water is absorbed mostly into SI but also the LI. The LI absorbs it by osmosis through cell walls into vascular capillaries inside villi. This allows the LI to....

finesse bowel movement composition and motility

What movement promotes absorption of food stuffs in the SI?

segmentation

What muscles are involved in promoting absorption of food stuffs in the SI?

muscularis mucosae, circular layer, and longitudinal layer

What structures are involved in the efficient absorption of food stuffs in the SI?

brush border

What happens in the digestive system when a lactose intolerant person consumes dairy?

undigested lactose retains fluid in feces and will result in bacterial fermentation and produce gas symptoms: -diarrhea -gas -bloating -abdominal cramps gets worse with age

Which hormones stimulate pancreatic bicarbonate secretion and growth of exocrine pancreas? test q

CCK and secretin

Which hormones inhibit gastric secretion? test q

secretin and GIP (gastric inhibitory peptide)

What is the path of carb digestion and absorption?

Which hormones are found in all 3 regions of SI?

secretin and CCK

Which hormone is found in duodenum and jejunum?

GIP

Which GLUT transporter is used to transport fructose from SI into an enterocyte?

GLUT5 (cotransporter with sodium)

Does protein digestion happen in mouth or esophagus?

Does fat digestion occur in the esophagus?