Homeostasis Continued (twice)

Question 1

in studies on rats, ventromedial hypothalamus (VMH) lesions caused obesity, this was believed to be a … center, since the animals ate significantly more and gained a lot of weight

• however, once they reached new, higher weights, their weights leveled off

Answer 1

satiety

Question 2

… lesions caused a refusal to eat and subsequent weight loss, this was believed to be a hunger center

• however, the rats did eventually begin eating again, and their weights stabilized

Answer 2

Lateral hypothalamus (LH)

Question 3

a circuit within the … of the hypothalamus is key in integrating peptide hormone signals from the body

Answer 3

arcuate nucleus

Question 4

fat cells release … into the blood stream to provide info to the brain about long-term energy reserves

• mice deficient in leptin or with nonfunctional leptin receptors become obese

Answer 4

leptin

Question 5

synthesized and related by endocrine cells of the stomach; reaches high levels before eating; drops off after eating; works as an appetite stimulant

Answer 5

ghrelin

Question 6

released by intestinal cells; reaches high levels after eating; works as an appetite suppressant

Answer 6

PYY 3-36

Question 7

increases rapidly during a meal, especially if the meal is high in fats and carbohydrates; signals reward with meals; blocks effects of ghrelin to reduce appetite

Answer 7

GLP- 1

Question 8

appetite signals from the hypothalamus converge on the nucleus of the … in the brainstem – a common pathway for feeding behavior

Answer 8

solitary tract (NST)

Question 9

… is a peptide released by the gut after feeding and acts on the vagus nerve to inhibit appetite

Answer 9

cholecystokinin (CCK)

Question 10

is a peptide hormone from the lateral hypothalamus that increases feeding

Answer 10

orexin

Question 11

act directly on the hypothalamic appetite regulation as well as in the periphery to increase hunger

Answer 11

endocannabinoids