Deck 12: Ingestive Behavior

Question 1

Which of the following is an example of the systems variable in a regulatory system such as a cooking oven?

A) the timer mechanism
B) the thermostat within the oven
C) the oven light
D) the air temperature in the oven
E) the highest temperature achieved by the oven

Answer 1

D

Question 2

When depleted of water, individuals only drink a certain amount before stopping; they do not drink until their cells have received the needed fluid. Satiety mechanisms monitor ___________ and stop the behavior in anticipation of replenishment to occur later.

A) the set point
B) the system variable
C) the detector
D) the negative feedback
E) the activity of the correctional mechanism

Answer 2

E

Question 3

A potent stimulus for producing osmometric thirst involves

A) evaporation from the lungs during the winter months.
B) vomiting during illness.
C) loss of blood after an automobile trauma.
D) ingestion of a bag of salted potato chips.
E) perspiration.

Answer 3

D

Question 4

Research shows that thirsty individuals have continued activation of the lamina terminalis after drinking, but the signals from the _____________ return to baseline levels.

A) anterior cingulate cortex
B) posterior cingulate cortex
C) parietal cortex
D) frontal cortex
E) primary somatosensory cortex

Question 5

A correctional mechanism for low blood volume involves

A) the movement of urine into the blood through the kidney.
B) movement of water into cells.
C) a fasting pumping action in the heart.
D) a slower pumping action in the heart.
E) contracting the muscles of the arteries and veins.

Question 6

The optimal value of the system variable in a homeostatic system is termed the

A) thermostat.
B) detector.
C) set point.
D) correctional mechanism.
E) homeostatic variable.

Question 7

If you feel warm in your room and prefer the temperature to be about 5 degrees cooler, your ideal temperature would be your

A) system variable.
B) detector.
C) set point.
D) correctional mechanism.
E) homeostatic variable.

Question 8

The process of ________ is involved in the regulation of the fluid that bathes our cells.

A) allostasis
B) homeostasis
C) hemostasis
D) negative feedback
E) hypovolemia

Question 9

A key reason why the volume of blood must be regulated within certain limits is that

A) reduced blood volume causes water to move out of cells.
B) reduced blood volume causes water to move into cells.
C) low blood volume leads to better pumping action in the heart.
D) low blood volume leads to heart failure.
E) high blood volume leads to low blood pressure.

Question 10

To maintain proper fluid balance, the body contains two sets of receptors, one that measures the volume of the ________ and the other that records the volume of the ________.

A) cerebrospinal fluid; cells
B) extracellular fluid; cells
C) blood; cells
D) interstitial fluid; intravascular
E) sodium ions; blood

Question 11

If the detector in a physiological system were to fail, one would expect

A) that the regulatory system would work, but more slowly than usual.
B) that positive feedback would spin the system out of control.
C) no change in the system variable.
D) that the set point would increase.
E) that the system variable would not be constant.

Question 12

Which fluid compartments must be precisely regulated within certain limits?

A) interstitial; intracellular
B) intracellular; cerebrospinal
C) extracellular; intracellular
D) intravascular; intracellular
E) transvascular; interstitial

Question 13

The primary location of osmoreceptors within brain is within the

A) zone incerta.
B) area postrema.
C) amygdala
D) nucleus accumbens.
E) lamina terminalis.

Question 14

Water loss from the body through evaporation results in

A) a loss of only interstitial fluid.
B) an increased concentration of solute within the interstitial fluid.
C) movement of water into the cells.
D) gain of water into the plasma.
E) loss of sodium from inside the cells.

Question 15

_____________ thirst is caused by loss of blood volume, whereas __________ thirst is caused by loss of cellular fluids.

A) Volumetric; osmometric
B) Osmometric; volumetric
C) Volumetric; isometric
D) Isometric; osmometric
E) Isometric; volumetric

Question 16

Intracellular fluid includes

A) interstitial fluid.
B) cell cytoplasm.
C) intravascular fluid.
D) cerebrospinal fluid.
E) extracellular fluid.

Question 17

When neurotransmitter is released and is detected by the autoreceptor, the autoreceptor triggers the cessation of neurotransmitter release. In terms of the regulatory system, this process is

A) positive feedback.
B) negative feedback.
C) the correctional mechanism.
D) the system variable.
E) the set point.

Question 18

Nearly two-thirds of the body's water is contained within the ________ fluid.

A) interstitial
B) intracellular
C) extracellular
D) intravascular
E) transvascular

Question 19

Osmoreceptors are specialized neurons that detect

A) changes in solute concentration of the interstitial fluid around the cell.
B) the concentration of renin within the blood.
C) angiotensin concentration in blood.
D) osmotic pressure within the blood plasma.
E) blood plasma solute concentration.

Question 20

Osmoreceptors change their firing rate in response to

A) the angiotensin concentration in blood.
B) the concentration of renin within the blood.
C) movement of water out of the osmoreceptor as the interstitial fluid becomes hypertonic.
D) reduced osmotic pressure within the blood plasma.
E) increased blood plasma volume.

Question 21

A fall in glucose levels causes the secretion of glucagon, which converts ____________ into _____________.

A) glucose; glycogen
B) glycogen; glucose
C) glucagon; glycogen
D) glucose; glucagon
E) glycogen; glucagon

Question 22

The carbohydrate reservoir in the liver is primarily reserved for use

A) by the central nervous system.
B) by the liver.
C) by the muscles.
D) in the support of nonshivering thermogenesis.
E) in general metabolism.

Question 23

Brain damage in humans that involves the lamina terminalis

A) produces an intense feeling of thirst that cannot be satisfied.
B) impairs the capacity of a person to experience thirst after injection of hypertonic saline.
C) blocks the neural signals generated by the atrial baroreceptors.
D) leads to increased water consumption.
E) leads to overconsumption of salt.

Question 24

The ________ regions of the lamina terminalis contain osmoreceptors.

A) medial and dorsal
B) OVLT and subfornical organ
C) area postrema and OVLT
D) commissural
E) posterior

Question 25

Activation of the anterior cingulate cortex would be expected to

A) blunt fluid intake in response to a hypotonic fluid challenge.
B) lower blood pressure.
C) produce overeating to obesity.
D) reflect the thirst state of the subject.
E) result in a hypotonic blood volume.

Question 26

Imaging studies in humans given a hypertonic thirst suggest that the ________ is involved in the unpleasantness of osmometric thirst, while the ________ detects the tonicity of the blood plasma.

A) anterior cingulate cortex; lamina terminalis
B) insular cortex; medial amygdala
C) lamina terminalis; anterior cingulate cortex
D) subfornical fornical organ; area postrema
E) medial amygdala; insular cortex

Question 27

The only bodily cells that do not require insulin in order to transport glucose across the cell membranes are

A) liver cells.
B) cells of the brain.
C) muscle cells.
D) pancreatic cells.
E) adipose cells.

Question 28

It is considered a bad idea to skip breakfast because

A) eating breakfast releases leptin, which activates brain cells.
B) fuel absorption is faster in the morning than in the afternoon.
C) the minerals eaten in a typical breakfast are important for energy metabolism.
D) the carbohydrate reserve of the liver can only be refilled during the morning.
E) the liver holds a limited amount of glucose for use by the brain, and this supply can be depleted after an overnight fast.

Question 29

Angiotensin within the blood stimulates drinking by acting on cells within the

A) subfornical organ.
B) nucleus of the solitary tract.
C) lateral hypothalamus.
D) kidney.
E) atria of the heart.

Question 30

An important physiological effect of angiotensin is to

A) end the consumption of water after a thirst episode.
B) release hormones that cause the kidneys to excrete water and sodium.
C) decrease blood pressure.
D) promote the consumption of salt.
E) suppress food intake.

Question 31

________ is secreted by pancreatic cells in response to ________.

A) Insulin; a fall in blood glucose
B) Glucagon; a rise in blood glucose
C) Amylin; entry of fat into the duodenum
D) Glucagon; a fall in blood glucose
E) Leptin; a fall in blood glucose

Question 32

The storage of glucose into glycogen in the short-term reservoir is stimulated by

A) glucagon.
B) glycine.
C) fatty acids.
D) insulin.
E) glycerol.

Question 33

The median preoptic nucleus

A) plays a role in feeding regulation in humans.
B) integrates most thirst-related stimuli.
C) is sensitive to neural signals generated by stomach stretch receptors.
D) is sensitive to information from the amygdala.
E) mediates the aversive aspect of intense thirst.

Question 34

When insulin is not present, glucose can be utilized by

A) liver cells.
B) cells of the brain.
C) muscle cells.
D) pancreatic cells.
E) adipose cells.

Question 35

Cells of the liver convert ____________ into _____________.

A) glucose; glycogen
B) glucagon; glucose
C) glucagon; glycogen
D) glucose; glucagon
E) glycogen; glucagon

Question 36

Our long-term fuel reservoir contains ________ and is located in ________.

A) glycogen; the liver
B) glycogen; the brain
C) triglycerides; fat cells
D) insulin; the pancreas
E) triglycerides; the liver

Question 37

Which of the following would activate the volumetric thirst system without an action on osmometric thirst?

A) evaporation of water from the lungs
B) severe constipation
C) loss of blood after an automobile trauma
D) ingestion of a bag of salted potato chips
E) evaporation of water from the skin

Question 38

When a person continues to fast beyond the short-term reservoir, the fat in the long-term reservoir is broken down into glycerol and fatty acids. Fatty acids can be metabolized by

A) the cells of the body.
B) the cells of the brain.
C) pancreatic cells.
D) neither the body or the brain.
E) both the body and the brain.

Question 39

When insulin is present, glucose can be utilized by

A) liver cells.
B) cells of the brain.
C) muscle cells.
D) neither the brain nor the body.
E) both the brain and the body.

Question 40

Zhang and colleagues report that ________ are mechanoreceptors that induce membrane ______.

A) volumetric receptors; spike discharge
B) osmoreceptors; depolarization
C) volumetric receptors; hyperpolarization
D) osmoreceptors; inhibition
E) osmoreceptors; hyperpolarization

Question 41

Plasma levels of ghrelin are highest _______ and lead to ________.

A) at the start of the morning; a craving for caffeine
B) after a meal; a craving for a cigarette
C) at the end of the evening; sleepiness
D) before a meal; eating
E) after a meal; consumption of a snack

Question 42

Hypoglycemia induced by an injection of ________ results in ????_______.

A) ghrelin; satiety
B) 2-DG; drinking
C) fenfluramine; conditioned satiety
D) insulin; eating
E) CCK; eating

Question 43

Nutrient detectors in the brain are sensitive to

A) decreasing levels of fatty acids.
B) glucoprivation.
C) lipoprivation.
D) both glucoprivation and lipoprivation.
E) lack of food in the digestive tract.

Question 44

The greatest degree of satiety would be expected for the situation involving

A) placing an amount of food directly into the stomach.
B) swallowing a mouthful of food that then exits via the esophagus.
C) swallowing a mouthful of food that is restricted to the stomach.
D) chewing a bite of food and then spitting it out.
E) distension of the stomach by an inflatable bag, in combination with infusion of nutrients directly into the duodenum.

Question 45

Participants had an infusion of a glucose solution. Participants reported increased fullness and reduced hunger when the solution was infused into the

A) liver.
B) brain.
C) large intestine.
D) small intestine.
E) stomach.

Question 46

Which of the following is correct regarding the role of the liver in the regulation of eating?

A) Lipoprivation within the kidney after 2-DG infusion leads to eating.
B) Cutting the inputs of the liver abolished the effects of 2-DG on eating.
C) Deprivation of lipid metabolism within the liver after mercaptoacetate treatment leads to eating.
D) Infusion of sodium chloride into the hepatic portal vein increases the activity of the afferent fibers arising from the liver.
E) The liver senses the level of ghrelin in the blood and acts to reduce eating.

Question 47

Which chemical or combination of chemicals would most stimulate eating behavior?

A) 2-DG
B) insulin and 2-DG
C) mercaptoacetate
D) 2-DG and glucagon
E) 2-DG and mercaptoacetate

Question 48

Detectors for glucose are located within the

A) liver.
B) duodenum.
C) gut.
D) forebrain.
E) kidney.

Question 49

The absorptive phase of metabolism is mostly controlled by release of

A) glucagon.
B) leptin.
C) CCK.
D) insulin.
E) glycerol.

Question 50

During the absorptive phase of metabolism,

A) blood glucose levels are lowered.
B) it has been some time since the person last ate food.
C) the pancreas secretes glucagon rather than insulin.
D) the liver converts glycogen to glucose.
E) blood glucose levels rise, which triggers the release of insulin by the pancreas.

Question 51

Match up the correct behavior with the condition that precedes it.

A) mercaptoacetate; drinking
B) insulin; drinking
C) insulin; sexual behavior
D) mercaptoacetate; eating
E) 2-DG; drinking

Question 52

Match the correct behavior with the condition that precedes it.

A) meracaptoacetate; drinking
B) insulin; drinking
C) insulin; sexual behavior
D) ghrelin; eating
E) 2-DG; drinking

Question 53

The liver sends information about available glucose and fatty acid levels to the brain via the ____________ nerve.

A) trigeminal
B) glossopharyngeal
C) vagus
D) hypoglossal
E) accessory

Question 54

Sensory factors that can influence satiety include

A) texture.
B) taste.
C) temperature.
D) temperature and taste.
E) temperature and texture.

Question 55

During the fasting phase of metabolism,

A) blood glucose levels are increased.
B) body cells are able to use glucose.
C) the pancreas secretes ghrelin rather than insulin.
D) the liver converts glucose to glycogen.
E) the pancreas secretes glucagon rather than insulin.

Question 56

Cholecystokinin

A) inhibits gastric contractions.
B) acts to stimulate eating via the ventromedial hypothalamus.
C) stimulates contraction of the gallbladder and pylorus.
D) inhibits eating.
E) blood levels are related to the sugar content of a meal.

Question 57

One explanation for why it is hard to maintain a low-calorie diet is that

A) food restriction elevates insulin release, which triggers feeding.
B) we are fundamentally too lazy to exercise.
C) starvation releases dopamine, which makes us happy.
D) food restriction elevates ghrelin release, which triggers hunger.
E) low calorie foods suppress ghrelin secretion.

Question 58

The primary hormone associated with the absorptive phase of metabolism is

A) glucagon.
B) CCK.
C) ghrelin.
D) insulin.
E) cortisol.

Question 59

If ghrelin levels remain high continuously, an individual would likely experience

A) continuous eating behavior.
B) cessation of eating behavior.
C) normal eating behavior, neither too much or too little intake.
D) binge eating followed by purging.
E) starvation.

Question 60

We know that nutrient receptors are located within the intestines because

A) injection of nutrients into the duodenum will induce eating.
B) infusion of fatty acids into the duodenum increases the firing rate of afferent axons from the gut.
C) infusion of amino acids into the stomach increases the firing rate of afferent axons from the gut.
D) infusion of glucose into the duodenum increases the firing rate of afferent axons from the gut.
E) eating is not altered by surgery that cuts the gut afferents.

Question 61

Electrical stimulation of the lateral hypothalamus

A) elicits eating and drinking.
B) inhibits food intake.
C) produces sham feeding.
D) elicits repetitive chewing movements.
E) is an intensely aversive stimulus.

Question 62

Which behavioral capacity below is retained in the decerebrate rat?

A) the capacity to approach food
B) the capacity to seek out and eat solid food
C) the capacity to respond to hunger and satiety signals
D) the capacity to swallow large bits of solid food
E) the ability to reject sweet tasting foods

Question 63

Which of these is a substance that would trigger hunger?

A) ghrelin
B) PYY
C) CCK
D) leptin
E) melatonin

Question 64

Electrolytic lesions of the ventromedial hypothalamus ________, whereas electrical stimulation ________.

A) impair sexual behavior; elicits repetitive bouts of copulation
B) inhibit eating; produces overeating
C) elicit repetitive bouts of copulation; impairs sexual behavior
D) produce overeating to obesity; inhibits eating
E) activate thermogenesis; induces shivering

Question 65

The effects of neuropeptide Y on ________ are localized within the ________.

A) eating; lateral hypothalamus
B) metabolism; lateral hypothalamus
C) eating; amygdala
D) eating; paraventricular hypothalamus
E) metabolism; arcuate hypothalamus

Question 66

There are many substances in the brain and body that trigger hunger. This one, however, triggers hunger even if giving into that hunger involves eating bitter foods or receiving shocks to the mouth during eating.

A) MCH
B) orexin
C) ghrelin
D) peptide YY
E) NPY

Question 67

Administration of endocannabinoids, substances related to THC, stimulates eating by

A) inactivating ghrelin receptors.
B) blocking cholinergic receptors in the brain stem.
C) increasing the release of MCH and orexin.
D) activating MC4-receptors.
E) decreasing the release of MCH and orexin.

Question 68

Leptin inhibits eating via

A) blockade of the entry of insulin into brain.
B) activation of CCK receptors in brain.
C) inhibition of NPY, AGRP, and orexin neurons within the hypothalamus.
D) increasing the release of NPY in the hypothalamus.
E) inducing the stomach to release more ghrelin.

Question 69

In the experiment by Tordoff and Friedman (1988), reduced eating in a hungry rat was noted after

A) infusions of glucose or fructose into the hepatic portal vein.
B) removal of nutrients from the stomach.
C) the investigators cut the hepatic branch of the vagus nerve.
D) placement of nutrients directly into the stomach.
E) 2-DG was injected into the hepatic portal vein.

Question 70

The ob mouse is obese because it lacks the gene that normally produces

A) CCK.
B) leptin.
C) insulin.
D) peptide YY.
E) glucagon.

Question 71

Habitual marijuana smokers often experience "the munchies" due to THC being an agonist for

A) NPY.
B) CART.
C) endocannabinoids.
D) ghrelin.
E) leptin.

Question 72

Targeted mutation in mice that prevented the production of insulin receptors in the brain without affecting their production elsewhere in the body resulted in mice that

A) experienced diabetes.
B) lose a great deal of weight.
C) showed behavior similar to post traumatic stress.
D) maintained body weight for an extended period of time.
E) became obese.

Question 73

Studies of feeding using decerebrate rats indicate that

A) the feeding circuits for chewing are contained within the forebrain.
B) CCK acts on frontal cortex to stimulate eating.
C) the brainstem contains circuits that allow a rat to chew and to swallow.
D) decerebrate rats are unable to chew, swallow, or distinguish tastes.
E) the circuits controlling ingestion lie forward to the brainstem.

Question 74

The entry of ingested food into the duodenum can suppress further eating via

A) the inhibition of gastric emptying.
B) the suppression of ghrelin secretion from the stomach.
C) activation of sympathetic nerve fibers that innervate the liver.
D) the secretion of insulin from the duodenum.
E) suppression of CCK release from the stomach.

Question 75

Ghrelin acts on ________ neurons to stimulate feeding.

A) NPY
B) angiotensin
C) MC4 receptors
D) leptin
E) agouti-related peptide

Question 76

Which pair below act as orexigens?

A) NPY; insulin
B) ghrelin; CART
C) CCK; ghrelin
D) CART; alpha-MSH
E) NPY; AGRP

Question 77

The brain interprets increased blood levels of insulin as a(n)

A) hunger signal.
B) indicator of the entry of fat into the duodenum.
C) indicator that the body is in the fasting e phase of metabolism.
D) satiety signal.
E) indicator that the stomach is full.

Question 78

The peptides ________ and ________ act in the hypothalamus to increase eating in the rat.

A) insulin; CCK
B) serotonin; CCK
C) NPY; leptin
D) orexin; melanin-concentrating hormone
E) CCK; ghrelin

Question 79

Ob mice lack which satiety signal?

A) CCK
B) leptin
C) insulin
D) peptide YY
E) glucagon

Question 80

Which terms below are synonymous?

A) orexins; hypocretins
B) insulin; glucagon
C) adrenaline; noradrenaline
D) NPY; CCK
E) satiety; hunger