Eating behavior - Biological explanations of eating Flashcards
what are the biological explanations for eating behavior?
neural and hormonal
what is leptin?
hormone produce by adipose/fat cells
what are fat cells named?
adipose cells
does leptin stimulate hunger or satiety?
satiety
explain the cycle of leptin in hunger cycle
1) leptin = hormone produced by adipose
2) levels of leptin in the blood increases with fat cells
3) this increase is detected by the VMH
4) if levels increase to a certain point the individual feels full and stops eating
what is Ghrelin?
hormone secreted by the stomach
explain the role of Ghrelin in the hunger cycle
1) Ghrelin is secreted by the stomach
2) marks how long since we have eaten
3) amount produced is proportional to how empty the stomach is
4) ghrelin levels are detected by the part of the hypothalamus called arcuate nucleus
5) when ghrelin reaches a certain point the arcuate nucleus send signals to LH
6) the LH secretes neuropeptide
7) this stimulates hunger
what transmitter stimulates hunger?
neuropeptide
what part of the brain detects rise in ghrelin levels?
a part of the hypothalamus called arcuate nucleus
what is homeostasis?
keeping of constant internal environment at a stable level
such as blood glucose and temperature
hypothalamus role in homeostasis
monitors and controls the internal environment specifically, the glucose-sensing neurons within the hypothalamus detects fluctuations in blood glucose levels
it influences the secretion of insulin and anti-insulin hormones which effect blood-glucose levels
what brain structures provide homeostasis?
lateral hypothalamus
ventromedial hypothalamus
role of VMH in homeostasis of hunger
detects a rise in blood glucose levels and inhibits feeling of satiety to stop a person eating
role of LH in homeostasis of hunger
detects a drop in blood glucose levels and triggers feeling of hunger so people eat
explain the neural homeostasis cycle to trigger eating
optimum blood glucose levels
drop in BG
LH detects change
feel hungry
glucose levels rise
