I. Hunger, Eating, and Healthy part 3 Flashcards
Explain what the following hypothalamic regions were thought to be associated w/? Why were they proven incorrect?
a) lateral hypothalamus
b) ventromedial hypothalamus
a) feeding center that would cause eating and drinking.
- lesion = lack of responsiveness to sensory input in general
b) a satiety center that would control the act of feeling full.
- lesion = ate more b/c of weight gain not gaining weight due to eating more
Lesioning the ventromedial hypothalamus caused rats to eat more in order to compensate for the added fat which dismissed the idea of it being the satiety centre. What was another reason for this dismissal?
the lesion resulted in damage in the paraventricular nucleus which showed to have the same effect when was lesioned independently
Match the following terms + explain each
a) aphagia
b) hyperphagia
c) adipsia
1. lateral hypothalamus
2. ventromedial hypothalalmus
- a) stop eating
c) stop drinking - b) excessive eating
Which of the following does damage to the paraventricular nucleus cause
a) aphagia
b) hyperphagia
c) adipsia
d) hyperadipsia
b
Describe the following. Which ones are associated w/ the paraventricular nucleus vs the arcuate nucleus?
a) melanocortin receptors
b) neuropeptide Y (NPY)
c) pro-opiomelanocortin (POMC) neuron
d) insulin receptors
e) leptin receptors
f) melanocortins
- Paraventricular nucleus
a) DEC hunger when activated
f) class of peptides that acts as a ligand to a) - arcuate nucleus
b) a peptide that causes hunger when released
c) neurons that produce melanocortins
d) receptor that is on the POMC –> DEC hunger
e) receptor that is on the NPY –> INC hunger
put the following in order wrt hunger + satiety signals
a) brain
b) bloodstream
c) gastrointestinal sys
d) response to blood signal
c -> b -> a -> d
What are the 5 feeding inhibitors?
- CCK - colecytokinin
- leptin
- melanocortins
- alpha-melanocyte-stimulating hormone
- 5HT - serotonin
What are the 2 feeding promoters?
- ghrelin
- NPY - neuropeptide
How would someone speaking from the set pt theory describe the regulation of body weight? Is this true?
in the longterm body weight would remain stable, which is not realisitic
T or F - fat levels w/in the body has a specific set pt in each indiv
F - while the body doesn’t like change it can adapt preventing a fixed set pt to develope
How did the people of Okinawan disprove set pt theory?
These people consume 20% fewer calories than the average which has resulted in a lower death rate and more longevity. Showing that its healthier to consume less calories
There was a rat exp where the following groups were presented w/ a certain amount of food given. Which group presented w/ the best health benefits?
a) ad libitum
b) 25% reduction
c) 55% reduction
d) 65% reduction
d
Describe diet-induced thermogenesis
the efficiency of NRG being used by the body in response to the level of body fat
According to Diet-induced thermogenesis, what would be the result of the following?
a) eating less
b) eating more
c) exercising more
d) exercising less
a) + c) In response to the DEC of body fat the body will INC its efficiency in NRG utilization (use less NRG for the same stuff) resulting in a DEC of body temp
b) + d) In response to the INC of body fat the body will INC its efficiency in NRG utilization (use more NRG for the same stuff) resulting in an INC of bod temp
How does diet-induced theromogenesis explain the initial phase of weight loss followed by weight stabilization in weight-loss programs?
initially, you will lose body fat. Then in response to that loss, the body will INC its NRG efficiency in order to prevent further weight loss (trying to keep body weight the same)
What is the purpose of the body undergoing diet-induced theromogenesis?
homeostasis - to maintain a stable body weight
Describe what happens in each phase (color) wrt diet-induced theromogenesis based on this image
Green = you start to eat less resulting in a DEC of body fat
red = the body recognizes that DEC in body fat and attempts to prevent any further DEC by INC its NRG efficiency
orange = the reduced rate of the intake matches the NRG efficiency keeping the body fat amount stable
purple = when the diet is terminated you begin to eat more resulting in an INC of body fat due to the INC NRG efficiency
pink = the body recognizes the INC in body fat thus it DEC NRG utilization as a means to prevent further INC of body fat
At which pts is a new settling pt achieved?
a) green
b) red
c) orange
d) purple
e) pink
c + e
a) Describe the settling-pt view?
b) how does this differ from the set pt theory?
a) the level at which all the factors that influence body weight reach an equilibrium
b) set pt is a fixed pt at which equilibrium is achieved however settling pt is dynamic thus can change dep on the changes to those factors
Describe the obesogenic environment
all the factors in a person’s environment that contribute to obesity