Digestion

Front 1

Say something about backward movement or reverse peristalsis at the cardiac oriface.

Back 1

vomiting, rats cannot do it so they do not return to tastes that made them sick

Front 2

What is the cause of stomach ulcer?

Back 2

acid, bacterium Helicobacter pylori

Front 3

What is the use of bicarbonate secretion from the pancreas?

Back 3

neutralize acidy coming from stomach

Front 4

"Salt and glucose facilitate the absorption of water across the intestinal epithelium." Under what circumstances would this knowledge allow you to save somebody's life?

Back 4

give someone with Cholera Gatorade before EMS personnel come to hook up an IV

Front 5

In a healthy person, urobilinogen is eliminated via the urine and (how else?).

Back 5

in the feces

Front 6

Facilitated by bile salts and catalyzed by lipase, triglyceride plus two water molecules is converted into (what three molecules?) in the intestinal lumen?

Back 6

a monoglyceride plus two fatty acids

Front 7

Obese mutant mice are deficient in leptin. Answer either (1) where (in a normal animal) leptin is made or (2) what part of the brain it affects.

Back 7

adipose tissue, arcuate nucleus of hypothalamus

Front 8

Why would it be useful for chief cells to have pepsinogen rather than pepsin in their secretory vesicles?

Back 8

so it does not break down proteins until it is in the stomach

Front 9

Proteins are broken into amino acids, and these are what move across the basolateral border of the intestinal epithelium. How does this differ for the apical surface?

Back 9

di- and tri-peptides also move across the brush border

Front 10

Why would a barbiturate have a stronger effect on a person who had not been taking barbiturates than on a person who had been taking barbiturates?

Back 10

detoxifying enzymes in smooth ER (microsomal fraction) of liver cells are inducible

Front 11

What, if any, type of polymer would be broken into monomers if given enough time in the presence of salivary amylase?

Back 11

starch

Front 12

Chief cells: answer EITHER (1) What is the name of the zymogen (precursor) in the granules of these cells. (2) Acid secreted (from what cell?) helps to form the active enzyme from the precursor?

Back 12

pepsinogen, parietal

Front 13

A SEVERE stomach disorder was once attributed to excess stomach acid. A further elucidation of this disorder was worthy of the 2005 Nobel prize in medicine (awarded to Marshall and Warren). Answer either (1) What disorder? Or (2) What was the cause of the disorder they discovered?

Back 13

ulcer, bacterium (Helicobactor pylori)

Front 14

Enzyme activity as a function of pH: describe the graphs for pepsin vs. salivary amylase.

Back 14

peaks are at 2 and 7 respectively

Front 15

Say something about how or where trypsin is activated.

Back 15

trypsin is activated in the intestinal lumen by chopping a fragment from the zymogen under the influence of enderokinase on the brush border (or by trypsin that has already been activated)

Front 16

In reference to lipase in the intestinal lumen, tell me either (1) What is the source of lipase? Or (2) What are the products when it acts on a triglyceride?

Back 16

pancreas, monoglyceride plus two fatty acids

Front 17

Why is the function of the hepatic portal vein so important?

Back 17

It delivers materials absorbed from the intestines to the liver for detoxification

Front 18

Amino acids stimulate G cells to release gastrin. State one of the secretions that result from this.

Back 18

One cell (ECL cell) puts out histamine causing parietal cell to put out HCl

Front 19

Using the correct terminology about the drug's affect on appetite (hunger), tell me about amphetamine.

Back 19

it is anorexogenic (it causes anorexia)

Front 20

WARFarin: Answer EITHER (1) Why is a substance like this effective for poisoning rats when, otherwise, it is difficult to poison a rat? Or (2) Why might it be given, in lower than poisonous doses, to a person?

Back 20

They will avoid the taste of something that makes them sick but the delayed anticoagulant action is not noticed (until it is too late), anticoagulants decrease the chance of a thrombus or an embolism

Front 21

Absorption of what important substance from the gut is disrupted by cholera toxin?

Back 21

water

Front 22

Why is it useful to have a lot of mitosis in the crypts of intestinal villi?

Back 22

Intestinal cells digest themselves and need to be replaced

Front 23

"In digestion, we break proteins down into amino acids for absorption." How would you modify that statement for the apical membrane of intestinal epithelial cells.

Back 23

Dipeptides and tripeptides also cross this membrane

Front 24

Why is the function of the microsomal fraction of hepatocytes so important?

Back 24

Detoxify drugs, alcohol, etc

Front 25

Loss of what hormone would cause an adrenalectomized animal to crave salt?

Back 25

aldosterone

Front 26

What is the function of the "microsomal fraction" in liver cells?

Back 26

detoxify

Front 27

Mitosis in the crypt of the villus is needed because of a short life expectancy of which cells?

Back 27

intestinal epithelial cells

Front 28

Repeated fatty metamorphosis of liver from alcohol binges leads to what scarring disorder?

Back 28

cirrhosis

Front 29

In addition to facilitated diffusion at the basolateral cell surface, what is necessary for glucose transport in kidney tubule and intestinal cell? (Include process and location.)

Back 29

apical cotransport with Na+

Front 30

What hormone from adipose tissue contributes to weight regulation?

Back 30

leptin

Front 31

The opposite of dehydration synthesis (condensation reaction) happens in digestion. What is this called?

Back 31

hydrolysis

Front 32

What is the optimum pH for pepsin?

Back 32

very acidic (2)

Front 33

Recycling of what kind of cell contributes to the dark color of feces, the yellow color of urine and the yellow skin in jaundice?

Back 33

RBCs

Front 34

What is a zymogen?

Back 34

inactive forms of digestive enzymes

Front 35

Where does trypsinogen come from?

Back 35

pancreas

Front 36

Cholera toxin affects the level of what famous "second messenger" in the intestinal epithelium?

Back 36

cAMP

Front 37

The portal vessel in the digestive system connects the intestine (where absorption takes place) to that organ?

Back 37

liver (its the hepatic portal vessel)

Front 38

Jaundice is a symptom of a disorder of what organ?

Back 38

liver

Front 39

What is the function of cholecystokinin (CCK)?

Back 39

hormone in digestion, slows gastric emptying, cranks up pancreatic secretions

Front 40

What is the function of salts of cholesterol made by the liver and secreted into the small intestine?

Back 40

emulsify fats

Front 41

In the intestine and the kidney tubule, three processes are needed for glucose transport, (1) basolateral sodium pump, (2) basolateral facilitated diffusion, and (3) apical... [yourturn].

Back 41

glucose/sodium cotransporter

Front 42

Cholera toxin interferes with water transport in the intestines in a mechanism utilizing what famous "second messenger?"

Back 42

cAMP

Front 43

What is the name of the lymph vessel in the intestinal villus that is important if absorption of fat?

Back 43

lacteal

Front 44

Many factors including hormones control gastric emptying via what "valve?"

Back 44

pyloric sphincter

Front 45

When I was in first grade, we were told to keep a saltine cracker in our mouth and notice that eventually it tasted sweet. What enzyme is responsible for this?

Back 45

amylase

Front 46

You swallow a bolus, and it gets broken apart and mixed with lots of fluid. What is the name of the fluid mixture emptying into the intestine?

Back 46

chyme

Front 47

What do you call the inclusions in pancreatic acinar cells with reference to the fact that they contain precursors of enzymes?

Back 47

zymogen granules

Front 48

What is the name biochemists use for the smooth endoplasmic reticulum of liver cells responsible for detoxifying toxins?

Back 48

microsomal fraction

Front 49

Where are the dipeptidases and tripeptidases responsible for the final breakdown of proteins to amino acids in digestion?

Back 49

inside the intestinal cell

Front 50

If one glucose transporter is on the brush border, where (specific cell surface) is the other?

Back 50

basolateral

Front 51

In a healthy person, what is the fate of bilirubin after it arrives at the liver?

Back 51

converted and out in feces

Front 52

What is the source of the digestive enzyme that converts fats to fatty acids plus a monoglyceride?

Back 52

lipase is from pancreas

Front 53

What does it mean to say a substance is orexigenic?

Back 53

makes you want to eat

Front 54

Where is the median eminence?

Back 54

Where hypothalamus connects to pituitary

Front 55

Argue that the effect of a hypothalamic lesion on weight regulation might result from loss of affect by interrupting the nigrostriatal tract. Be specific about what effect you are talking about and/or what part of the hypothalamus.

Back 55

weight loss from lateral hypothalamus lesion might be from not appreciatng the "goodness" of food

Front 56

List one (of the several) effect of gastrin.

Back 56

make parietal cell secrete HCl or chief cell secrete pepsinogen (or ECL cell secrete histamine)

Front 57

Why is a portion of the hypothalamus referred to as "supraoptic?"

Back 57

it is above optic chiasm

Front 58

In what molecular form is fat absorbed from the intestinal cell (to the body)?

Back 58

triglycerides combined with protein in droplet called chylomicron

Front 59

Name an enzyme derived from a pancreatic precursor that is an endopeptidase.

Back 59

trypsin, chymotrypsin

Front 60

What are zymogen granules in pancreatic acinar cells?

Back 60

contain precursors of digestive enzymes like trypsinogen

Front 61

"Enterokinase on the brush border cleaves trypsinogen to activate trypsin." Translate.

Back 61

the microvilli on intestinal epithelial cells activate the proteolytic enzyme by cutting off a peptide fragment

Front 62

What is the purpose of bicarbonate secretion by the pancreas?

Back 62

neutralize stomach acid for intestine

Front 63

"Proteins are hydrolyzed into singal amino acids to be absorbed by intestinal epithelial cells and passed into the blood stream." Why is this not the whole truth?

Back 63

peptides of 2 and 3 aminoacids can be taken into cell for final breakdown in cell

Front 64

As heme is broken down, one of the products is bilirubin. What becomes of this substance?

Back 64

conjugated to gluconuride, converted to uropilinogen, put out in feces and urine

Front 65

The hepatic portal vein carries blood from the small intestine to where?

Back 65

liver

Front 66

What happens to a monoglyceride inside a cell of the small intestine?

Back 66

two fatty acids added (converted to fat (triglyceride)

Front 67

Gastrin stimulates secretions of parietal and chief cells. Name these secrtetions.

Back 67

HCl, pepsinogen

Front 68

What would be the cause of death if you had cholera, and how might you prevent death if you were nowhere near medical help?

Back 68

dehydration, gatorade

Front 69

What specialization in the stomach regulates gastric emptying into the small intestine?

Back 69

pyloric sphincter

Front 70

"Leptin causes a decrease of the orexigenic neuropeptide Y from the arcuate nucleus." Translate.

Back 70

neuropeptide Y from that part of the hypothalamus would cause the opposite of anorexia, so the protein leptin should be good for weight loss

Front 71

Go on a drinking binge and there will be fat in the liver the next day. Biochemically, how did that fat get there?

Back 71

alcohol -> aldehyde -> acetic acid (adds 2 carbons to a fatty acid)

Front 72

The same sort of drug given to heart patients to decrease the likeliness of a thrombus is very useful as a rat or mouse poison. Why?

Back 72

rats avoid tastes of foods that made them sick and anticoagulants work so slowly that they never make the association

Front 73

Bilirubin results from what ativity in what organ?

Back 73

derived from red blood cell hemoglobin, handled by liver

Front 74

What molecules make up the chylomicrons that are transported to the lacteal?

Back 74

triglycerides plus proteins

Front 75

Why are ob/ob mice obese?

Back 75

lack leptin

Front 76

What is the word for the coordinated wave of smooth muscle contraction that propels a bolus of food forward through the esophagus?

Back 76

peristalsis

Front 77

Baking soda would be a quick fix for what digestive ailment?

Back 77

"heartburn" caused by excessive stomach acid

Front 78

The appropriate signalling that involves cAMP for water absorption in the intestine is disrupted by what toxin?

Back 78

cholera

Front 79

After enzymes act on proteins in the intestinal lumen, list every product of that degradation that gets absorbed into the intestinal cell.

Back 79

single amino acids, dipeptides, tripeptides

Front 80

Conversion to what molecule explains why alcohol consumption can cause fat deposits in the liver?

Back 80

acetic acid (acetyl coA)

Front 81

"Gastrin stimulates parietal cells to secrete HCl." In parallel, it stimulates chief cells to secrete what?

Back 81

pepsinogen

Front 82

Why might the nigrostriatal dopamine tract have to do with hunger/satiety?

Back 82

contributes to motivation and affect

Front 83

What indication of body energy stores would cause leptin to increase?

Back 83

increased fat in adipose tissue

Front 84

"Agouti-related protein (AgRP) is orexigenic." Translate.

Back 84

this protein, oddly related to coat color, increases desire to eat

Front 85

"The product of the parietal cells activates the product of the chief cells." Elabortate

Back 85

parietal cell puts out acid which converts chief cell's pepsinogen into pepsin

Front 86

Why do some people occasionally drink a spoonful of baking soda mixed in water?

Back 86

baking soda = "bicarbonate of soda" = sodium bicarbonate, neutralizes stomach acid, helps with "heart" burn

Front 87

Away from emergency responders, what can you offer better than water to rehydrate a cholera victim?

Back 87

an electrolyte-glucose coctail such as Gatorade is absorbed better

Front 88

The microvilli on the surface of the intestinal cells are so famous that they have a name. What is that name?

Back 88

brush border

Front 89

Why, in terms of chemistry or process involved, does hepatitis lead to jaundice?

Back 89

inflammation has hepatocytes spill bilirubin (from hemoglobin recycling) into blood instead of feces

Front 90

In terms of fat digestion, what is transported across the basolateral surface of the intestinal epithelium into the lacteal?

Back 90

chylomicrons are triglycerides bound to proteins

Front 91

You were shown that amino acids stimulated the G cell to release gastrin which caused the production of (what?) (also where?).

Back 91

(via an intermediate ECL cell that releases histamine): acid in the stomach

Front 92

"Agouti-related peptide (AgRP) is orexigenic." Explain to someone who is not as sophisticated as you (are supposed to be) either: The meaning of orexigenic. Or. How (in the heck) did we get on the topic of agouti?

Back 92

opposite of anorexigenic, stimulating appetite. Although agouti has to do with coat color, this protein which is orexigenic is like agouti, hence that seemingly esoteric naming

Front 93

For glucose absorption from the gut, what is the process on the basolateral surface that requires energy?

Back 93

the sodium pump

Front 94

"In histology, you see zymogens located in acinar cells." What does that have to do with digestion?

Back 94

These granules house the precursors of digestive enzymes of the pancreas

Front 95

Relate the hepatic portal vessel with the "microsomal fraction" (smooth endoplasmic reticulum of the hepatocyte).

Back 95

This gives the liver a chance to detoxify what is absorbed from the gut before it gets to the systemic circulatio

Front 96

"A lesion in the lateral hypothalamus (LH) gives you a thin rat, hence the LH is a hunger center." What have we learned since this conclusion was first reached that gives us a different view of the role of the LH?

Back 96

The LH has the dopamine tract that is useful in motivation (affect) in general

Front 97

Make an argument that salivary amylase is not of significant value in the overall hydrolysis of macromolecules for digestion.

Back 97

swallow soon and inactivated in stomach

Front 98

At what structure is gastric emptying controlled.

Back 98

pyloric sphincter

Front 99

"Proteins are broken down into amino acids and that is what is absorbed." Why is this not the whole truth regarding the apical surface of the intestinal epithelial cell?

Back 99

uptake of di and tri peptides

Front 100

Why is jaundice one sign of hepatitis?

Back 100

b/c bile pigments build up in blood

Front 101

"Everybody knows about (what structure that feeds blood from the small intestine to the liver?) if they took a course like this."

Back 101

hepatic portal vein

Front 102

What are the products when lipase acts on triglyceride in the lumen of the small intestine?

Back 102

2 fatty acids and monoacyl glycerol

Front 103

With the G cell, the ECL cell, histamine, amino acids, and the vagus nerve, answer either (1) What hormonal system?, (2) That hormone affects what cell type? Or (3) That cell type releases what?

Back 103

gastrin, parietal, HCl

Front 104

Homozygous obese (ob/ob) ­p; Answer either (1) What is the protein product of that gene that is missing? Or (2) What tissue releases this product (in non-mutant mice)?

Back 104

leptin adipose

Front 105

Why would it be useful to have the proteolytic enzymes in digestion stored as inactive precursors in the granules (zymogens) in the cells that secrete them?

Back 105

so enzymes do not digest their granules and cells

Front 106

Why are enzymes on the brush border important for trypsin function?

Back 106

they convert trypsinogen to trypsin

Front 107

Heme is broken down to iron, carbon monoxide and (fill in the blank). (OK if you say the immediate product or subsequent steps in the processing of this product.)

Back 107

biliverdin, bilirubin, bilirubin glucuronide (conjugated bilirubin)

Front 108

To bring fats into the lacteal, what, in fact, is transported across the basolateral membrane of the intestinal epithelium cell?

Back 108

chylomicrons (tryglycerides and proteins)

Front 109

Why was it relevant to remind you about Parkinson's disease after saying that lesions of the lateral hypothalamus caused the rat to lose weight?

Back 109

lesions would interrupt nigrostriatal dopamine tract causing loss of affect