Feb5 M2-Appetite and Obesity

Question 1

mouth main secretion

Answer 1

amylase by salivary glands

Question 2

stomach main secretion + other

Answer 2

• pepsinogen by chief cells (zymogen). becomes pepsin bc of low pH
• lipases too to make monoglycerides and FFAs

Question 3

pancreas main secretions

Answer 3

lipases, proteolytic enzymes, amylase

Question 4

gallbladder main secretion

Answer 4

bile

Question 5

2 detergents in bile and what they do

Answer 5

lecithin and bile salts. convert fat globules into very small droplets called micelles (emulsification) so that lipases can act on the fat

Question 6

main proteolytic enzymes fro mthe pancreas

Answer 6

trypsin, chymotrypsin, carboxypolypeptidase

Question 7

large intestine function

Answer 7

absorb water and NaCl and store feces

Question 8

what’s responsible for the preparation to digestion when you smell something or feel hungry

Answer 8

molecules called secretagogues. signaling peptides

Question 9

what cells secrete HCl in the stomach

Answer 9

parietal cells

Question 10

what controls HCl release by parietal cells in the stomach

Answer 10

• gastrin (secretagogue) from G cells of the end of the stomach
• vagus may stimulate gastric mucosa to make GRP (gastrin releasing peptide) to act on G cells and make gastrin

Question 11

how stomach can expand

Answer 11

stretch and pressure trigger vagus to brainstem to vagus reflex to accomodate

Question 12

2 secretagogues secreted upon entry of gastric chyme in duodenum and why

Answer 12

• secretin bc of low pH

- cholecystokin (CCK) bc of fat and aa content

Question 13

CCK and secretin function

Answer 13

• CCK + secretin: make pancreas secrete more

- CCK stimulates GB bile secretion

Question 14

where proteolytic enzymes of the small intestine (enteropeptidases, etc.) are located

Answer 14

on surface of epithelial cell

Question 15

first brake discovered and what it is (brake = signal regulating chyme propulsion in SI)

Answer 15

ileal brake. strong inhibition of SI peristaltis bc of fat

Question 16

why people with distal SI obstruction or high volume diarrhea (ex. caused by cholera) are vulnerable to hyovolemia and death

Answer 16

bc of large amounts of fluid secreted by GI tract and that is normally reabsorbed (and reabso is impaired)

Question 17

appetite vs hunger

Answer 17

hunger = uncomfortable feeling + interest in eating food
appetite = conscious desire to eat specific food

Question 18

what do we call eating triggered by anticipated pleasure

Answer 18

hedonic feeding behavior

Question 19

feeding and satiety centers in the hypothalamus

Answer 19

feeding centers = lateral nuclei

satiety centers = ventromedial nuclei, inhibit feeding centers

Question 20

leptin comes from where and what it does

Answer 20

from adipocytes. inhibits feeding centers

Question 21

ghrelin comes from where and what it does

Answer 21

peptide hormone from stomach. stimulates hunger (feeding center) and increases appetite

Question 22

CCK does what on hypothalamus

Answer 22

inhibits hunger (feeding, lateral center)

Question 23

name of hormones that increase feeding vs those that decrease feeding

Answer 23

increase feeding = orexigenic hormones

decrease feeding = anorexigenic hormones

Question 24

anorexia nervosa def

Answer 24

reduced food intake bc of fear of gaining weight, will to lose weight

Question 25

how hunger and satiety intensity may vary between people

Answer 25

hunger: may start eating as soon as feel hungry or only when feel very hungry
satiety: may stop eating as soon as they fill full or only after a while

Question 26

how obesity diagnosed

Answer 26

measure BMI (kg over height in m2)

Question 27

how risk varies with BMI

Answer 27

health risks increases proportionally with BMI and increases greatly over BMI of 30

Question 28

how important is fat distribution

Answer 28

greater health risk if central and abd fat but not as much if hips and rear end fat deposition

Question 29

waist definition

Answer 29

narrowest abd circumference (or halfway between iliac crest and costal margin)

Question 30

hip circumference def

Answer 30

widest part of the gluteal region

Question 31

central fat distribution def

Answer 31

WH ratio over 1 in men

WH ratio over 0.85 in women

Question 32

obesity strong risk factor for what other disease

Answer 32

type 2 diabetes

Question 33

metabolic syndrome def

Answer 33

combination of insulin resistance (doesn’t have to type 2 DM), high BP, CV disease promoting lipid profile and high uric acid

Question 34

why epidemic of obesity

Answer 34

• more sendentarity

- more use of processed foods and sugar-sweetened beverages

Question 35

who becomes obese

Answer 35

people living in obesity-promoting environment (obesogenic) and with obesity predisposition

Question 36

obesity and genetic

Answer 36

moderately strong genetic link (noticed strong familial links but no genes identified except a few rare). multifactorial and polygenic

Question 37

thrifty gene hypothesis

Answer 37

notion of a certain genetic profile suitable for food scarce environment but not that predisposes to obesity in the modern environment

Question 38

in who does obesity NOT occur

Answer 38

doesn’t occur in people who are genetically or metabolically predisposed to a resistance to excessive fat gain

Question 39

proof that a regulated and modifiable fat ‘‘set point’’ may exist

Answer 39

pregnant women gain 15-20 kg, 25% of which is fat

Question 40

steps to go about obesity as a physician

Answer 40

1. no negative bias
2. measure it + risks
3. how did it come
4. formulate a plan
5. exercise
6. diet

Question 41

how to measure obesity

Answer 41

BMI, WH ratio and check for risk factors (BP, diabetes, lipids, liver fat, sleep apnea)

Question 42

when are risk factors more important

Answer 42

when obesity is more severe and when there are other risk factors (like family history, high BP,..)

Question 43

when to consider gastric bypass surgery

Answer 43

severe and life long obesity with family history + unlikely to change + very bad risk factors with it (lipids, fatty liver) or comobordities

Question 44

2 types of exercise that work

Answer 44

• formal

- non-exercise associated thermogenesis