Digestive System And Disorders

Front 1

what organs are in the middle GI tract?

Back 1

the small intestine

Front 2

What are the 3 portions of the small intestine?

Back 2

1.duodenum - contains the openeing for the bile duct and main pancreatic duct
2. jejunum - where food is digested and abosrbed
3. ileum - where food is digested and absorbed

Front 3

What are the lorgans of the lower GI tract?

Back 3

1. cecum
2. colon
3. rectum
4. anal canal

Front 4

What are the layers of the GI wall?

Back 4

1. mucosal layer - inner layer, produces mucus that lubricates and protects inner surfacse
2. submucosal layer - (support) consisits of connective tissue containing blood vessels, nerves and strictures that secrete digestive enzymes
3. circular layer
4. longitudinal layer
5. peritoneum - outer layer

Front 5

what are the sublayers of the peritoneum?

Back 5

1. parietal peritoneum - in contact with abdominal wall
2. viseral peritoneum - covers stomach and intestines.. protects underlying tissue by secreting serious fluid to moisten and lubricate

Front 6

What is the mesentery?

Back 6

a double fold of peritoneum that suspend th jejunum and ileum. Contains blood vessles, nerves and lymphatic vessels that supply intestinal wall

Front 7

What is peristalsis?

Back 7

propelling movement from proximal to distal in stomach and small intestine. coordinated circulat nad lenthwise contractions

Front 8

What does gastresophageal spincter do?

Back 8

contraction prevents fastric reflux and hyatus of diaphram. relaxes during swallowing

Front 9

what do epithelial cells in esophagus secrete?

Back 9

mucus

Front 10

where is protien digesteion initated?

Back 10

stomach

Front 11

what is largest endocrine organ in the gody?

Back 11

the GI tract

Front 12

What does cholecytokinin do?

Back 12

secreted in duodenum and jejunum when products of protein digestion fatty acids are present. Stimulats contraction of ballbladder and secretion of pancreatic enzymes. inhibits food untake

Front 13

What is Gastrin?

Back 13

hormone produced by G cells in stomach. Stimulates gastric acid secretion

Front 14

What is Secretin?

Back 14

hormone secreted by mucosa of duodnum and jejunum that inhibits gastric acid secretion... release is stimulated by entry of acidic chyeme into small intestine

Front 15

What are the two types of glands in the stomach?

Back 15

1. oxyntic glands (or gastric) - in proximal section
2. pyloric glands - in antrum segment (distal

Front 16

what do oxyntic/gastric gland secrete?

Back 16

1. HCL (parietal/oxyntic cell)
2. pepsinogen (chief /peptic cells)... convereted to pepsin by HCL
3. intrinsic factor
4. mucous

Front 17

what do pyloric glands secrente

Back 17

- mostly mucus
-some pepsionogen and gastrin

Front 18

why is intrisic factor important?
what cells secrete it?

Back 18

-produced by parietal/oxyntic cells
-neseccary for B12 absorption

Front 19

What do parital/ oxyntic cells secrete?

Back 19

HCL and intrinsic factor

Front 20

what do peptic or cheif cells secrete?

Back 20

pepsinogen

Front 21

what regulates gastic secretions?

Back 21

1,.parasympathtic impules throug vagus nerve and gastrin enhance gastric secretions
2. sympathetic impulses triggered by food/ acid in small intestine inhibits gastric secretions

Front 22

what effect to parasympathetic impusles have on digetion?

Back 22

enhance gastric secretion by stimulateing gastrin release.

Front 23

where does the breakdown of fats begin?

Back 23

the small intestine

Front 24

what is main absorption function of large intestine?

Back 24

water reabsorption by osmosis

Front 25

what enzynes digest carbs?

Back 25

1. amylase (mouth and pancrease)
2.

Front 26

what is major site of fat absorption?

Back 26

uppper jejunum

Front 27

what enzyme breaks down fats?

Back 27

Lipase from pancrease

Front 28

where are proteins digested and by what enzymes?

Back 28

1. pepsin (stomach)
2. Pancreatic enzymes:
- trypsin
-chymotrypsin
-carboxypeptidase

Front 29

what are contents of pancreatic juise?

Back 29

1. bicarbonate ions - nuetralize acidic chyme
2. digestive enzymes:
-amylase
-lipase
-nucleases
-proteolytic enzymes: trypsin, chymotrypsin, carboxypepsidase

Front 30

what type of pancreatic cells produce digestive enzymes?

Back 30

Acini cells

Front 31

when are pancreatic digestive enzymes sent to duedunum?

Back 31

When acidic chyme eneres duodenum, mucous membranse releases secretin and cholecytokinin, which stimulate release of pancreatic juice to neutrailize acidic chyme

Front 32

what does protiens and fats in chyme stimulate?

Back 32

release of cholecytokinin by duodenom, which stimulates relsease of pancreatic juice

Front 33

what are the functional units of the liver?

Back 33

Hepatic lobules - hepatic cells radiationg out from a central vein, separated by vascualr channals (sinusoid). Hepatic cells modify blood composition by picking up chemicals

Front 34

what are the major functions of the liver?

Back 34

1. metabolism of carb, lipids and protiens
2. filters blood
3. destroys toxins
3. secretes bile - digestion

Front 35

whawhat are sinusoids?

Back 35

vascular channels that separate hepatic cells, where blood from digestive tract brings nutrients and macrophages remove bacteria... bllod then empties into central veins

Front 36

What is calanilculus?

Back 36

where bile is released from hepatic cells and carried to bile duct, where it is taken to gall bladder

Front 37

what is the path of bile?

Back 37

hepatic cells--> cnaliculus --> bile duct --> galbladder

Front 38

what are metabolic functions of liver with sugars, proteins and fats?

Back 38

1. Sugars :stored as glycogen, converted to glucose, used to make fats
2.Proteins : synthesized from amino acids; ammonia made into urea
3. Fats : oxidized for energy, synthesized, packaged into lipoproteins

Front 39

What is the composition of bile?

Back 39

bile salts(*only one impt for digestion)
pigments
cholesterol
electrolytes

Front 40

What is function of the gall bladder?

Back 40

-stores bile between meals, then releases into small intestine when sphincter musulce contracts

Front 41

when arwhen does gallbladder realse bile?

Back 41

stiumlated by cholecytokinin

Front 42

what is the function of bile?

Back 42

1. emulsifies fats so that lipases can work effectivley
2. aids in absorption of fatty acids, cholesterol, and fat-soluable vitamins

Front 43

what can lack of bile salts cause?

Back 43

poor lipid absorption
vitamin deficiencies

Front 44

what happens to bile after in intestines?

Back 44

In large intestine, convereted by bacteria to urobilinogen
-some lost in feces
-some reabsorbed in blood
- some returned to liver
- some filtered out by kidneys 00> urine

Front 45

-What are crypt of Lieberkühn?

Back 45

glands in small intestine

Front 46

Structure of the small intestine wall:

Back 46

Mucuous membrane lined with villi: ↑surface area (250 m2); aid in mixing and absorption
-Intestinal glands between villi(crypt of Lieber

Front 47

What are the functinos of the small intestine?

Back 47

Receives secretion from pancreas and liver
Completes nutrient digestion
Absorbs products of digestion (enterocytes)
Transports the residues to the large intestine

Front 48

What do small intestine microvilli do?

Back 48

Enzymes in microvilliperform final steps in digestion:
Lactase, sucrase, amylase, maltase, αdxtrimase
Villiabsorb monosaccharides, aminoacids, fatty acids, and glycerol
Fat molecules with longer chains if carbon atoms enter the lacteals of the villi

Front 49

what is the Ileocecal sphincter?

Back 49

controls movements of the intestinal contents from the small intestine into the large intestine

Front 50

what are the main functions of the large intestine?

Back 50

1. Reabsorbs water and electrolytes
2. Forms and stores feces
3. secretes mucus
-little or no digestive function

Front 51

what are enterocytes?

Back 51

- cover the villi of the small intestive and contribute to absorbtion and digestion
- secrete brush border enzymes

Front 52

what do brush border enzymes do?

Back 52

-released by enterocytes of small intestine
- break down disachharides to monosaccarides
-also breaks down polyptids

Front 53

Protein digestion overview:

Back 53

1. Stomach: pepsinogen
-Activated to pepsin by acid in stomach
-Breaks proteins into polypeptides
2. Duodenum: pancreatic trypsinogen
-Activated to trypsin in duodenum
-Breaks proteins into polypeptides
3. Brush border enzymes
Breaks polypeptides into 2–3 aminoacidpeptides
- Peptides absorbed into blood

Front 54

--Carbohydrate Digestion overview

Back 54

1. mouth - salivary amylase
2. SI -duodenum - pancreatic amylase: poly saccarids --> di
3. Brush border enzymes: di - mono, monosac absorbed into blood

Front 55

Fat Digestion overview"

Back 55

1. Dudenum - bile emulsifies
2. Deodenum - pancreatic lipase breaks trigly into glycerol and fatty acids
3. Jjeunum - packages fats as chylomicrons and passes to lymph

Front 56

Glocose transport from intestinal lumen into body fluids:

Back 56

1. Both Na+ and glucose must attach to carrier before transported into the cell
2. The concentration of glucose builds up in the intestinal cell until a diffusion gradient develops→ glucose move into the body fluids
-Sodium is transported out of the cell by the energy-dependent Na+/K+-ATPasepump. This creates the gradient needed to operate the transport system
-Water is passively absorbed along a concentration gradient generated by the absorption of solutes

Front 57

Digestion of which substance begins in the mouth?

Back 57

Carbohydrate digestion begins in the mouth with salivary amylase;
protein digestion begins in the stomach with pepsinogen; fat digestion begins in the small intestine with bile and pancreatic lipase

Front 58

How would fat digestion be affected if bile levels decreased?

Back 58

It would decrease
Bile emulsifies fat so that it can be more easily digested. Decreased amounts of bile would lead to decreased fat emulsification and decreased ability to break down/digest fats