Ingestive Behaviors

Question 1

ingestive behavior

Answer 1

correctional mechanisms that replenish the body’s depleted stores of water or nutrients

Question 2

intracellular fluid

Answer 2

2/3 of volume

Question 3

extracellular fluid

Answer 3

1/3 of the volume
2 types: intravascular and interstitial
a tiny bit of CSF also

Question 4

intravascular

Answer 4

part of the extracellular fluid; blood plasma

Question 5

interstitial

Answer 5

part of extracellular fluid: fluid that bathes the cells

Question 6

tonicity

Answer 6

the ability of a surrounding solution to cause a cell to gain or lose water via osmosis; movement of water from one place to another
relation between interstitial and intracellular
solute concentration determines movement in or out

Question 7

tonicity; hypertonic

Answer 7

if interstitial fluid is hypertonic this means more solute which means water moves OUT of cell; cells are shriveled up

Question 8

tonicity; isotonic

Answer 8

what we want
equal concentration on both sides (in and outside of the cell) so no movement

Question 9

tonicity; hypotonic

Answer 9

if interstitial fluid is hypotonic there is less solute so water moves INTO cells; cells are overfilled

Question 10

negative feedback loop of hunger

Answer 10

essential characteristic of regulatory mechanism; for an empty stomach = empty stomach triggers hunger which triggers eating with triggers satiation (opposite response)
stop behaviors in anticipation of replenishment
*Hunger negative feedback loop takes time to reach brain thats why we over eat we don’t feel full yet when we are = ~20 minute delay

Question 11

osmometric thirst

Answer 11

triggered by salty food; when tonicity of interstitial fluid increases
thirst is triggered by cell dehydration

Question 12

volumetric thirst

Answer 12

when intravascular (blood plasma) volume decreases (hypovolemia)
causes bleeding, vomiting, diarrhea (when blood plasma is low)
leads to: increased blood pressure, inhibition of water and sodium secretion

Question 13

hypovolemia

Answer 13

when blood plasma volume decreases

Question 14

natural dying

Answer 14

dehydration of cells is part of body’s natural dying process
if you give someone dying an IV it will enter their lungs and they will go into respiratory distress
reduction in eating: ketosis = results in reduced appetite and thirst, pain relief, euphoria

Question 15

ghrelin

Answer 15

hormone released by the stomach when individuals are fasting or the digestive system is empty
binds to receptors in the hypothalamus and activates orexin producing neuron
stimulates hunger/eating behaviors
“stomach growling”
increases before eating decreases after eating (satiation mechanism)

Question 16

low ghrelin

Answer 16

high cortisol = stress and anxiety = body thinks you are starving

Question 17

high ghrelin

Answer 17

low cortisol = reduced stress and anxiety

Question 18

Prader-Willi Syndrome

Answer 18

genetic multisystem D/O
hyper-phagia due to excessive levels of ghrelin
they never feel satiated

Question 19

ghrelin peaks

Answer 19

ghrelin peaks at certain times of the day
highest peaks at 8 am, ~12pm and ~ 6pm (breakfast lunch and dinner)

Question 20

Lateral hypothalamus and hunger

Answer 20

when destroyed you stop eating and drinking
when activated = overeat
produces orexin = motivation to eat

Question 21

ventromedial hypothalamus and hunger

Answer 21

when destroyed = overeat
when activated = suppression of eating

Question 22

Weight loss

Answer 22

reduced for first 8 months of adjustable gastric band = reduced volume in stomach = ghrelin levels drop sooner
~8mo = 53% higher than pre surgery (gastric band) not in gastric bypass

Question 23

Wegovy

Answer 23

semaglutide; FDA approved 2021; weight loss medication that augments insulin secretion to inhibit release of glucagon; increased risk of gall bladder, kidney, diabetic retinopathy, depression, and SI

Question 24

Obesity

Answer 24

complex chronic disease which requires medical attention
AMA: BMI > 30 (flawed)
since 2000: 2x in adult 3x in adolescents
14th in world (US)

Question 25

food addiction

Answer 25

dopamine levels change results in withdrawal symptoms

Question 26

risk factors for obesity

Answer 26

diabetes hypertension and cholesterol carry higher burden BUT normal cholesterol and blood pressure can still develop heart disease

Question 27

sensory and social factors of eating

Answer 27

the older you get = decrease in taste
larger plate size = increased intake
“pepsi paradox” = branding is important VMPFC activates for loyalists

Question 28

deficiency of vitamin D

Answer 28

increase in depression and negative emotions
~40-50% of men and women in denver metro have vitamin D deficiency
increased melanin = the harder it is to synthesize vitamin D
current use with anti-depressants = supported

Question 29

Magnesium Deficiency

Answer 29

w/stress = increased agitation, anxiety, sleeplessness, headaches and apathy
can treat restless leg syndrome
slow response time to reach steady state via oral supplement (~30 weeks)

Question 30

omega-3 fatty oils

Answer 30

strong evidence for added on treatment for depression
some evidence for ADHD

Question 31

anorexia

Answer 31

restricted access = starvation = anorexia
highly hereditary (twin studies show 58-76%)
risk increased for premature birth or birth trauma
associated with:
loss of gray and white matter in brain,
enlarged ventricles and widened sulci (shrinkage of brain tissue),
inhibited emotional facial expression despite reporting similar or more intense emotions
tissue loss can be reversed with successful treatment of the ED
more women than men
treatment: CBT, increased eating speed, stimulation of AAC

Question 32

Bulimia Nervosa

Answer 32

associated with:
decreased blood flow to the Precuneus
amygdala activation: higher activation when eating than when control; stable when eating post-fast
vomiting only eliminates ~25% of calories consumed BUT prolonged dehydration and electrolyte depletion = 5x higher risk of heart attack, overall risk of hypovolemic shock, kidney failure and UTI

Question 33

bulimia feedback loop

Answer 33

DA, 5HTP and NE
anticipation of binge –> consumption of “junk” food –> anticipation of purge –> purge (i.e., vomiting)

stress = binge-purge cycle = receptor down regulation and repeat