Q&A Hero

Q: Leptin directly activates receptors in the part of the hypothalamus known as the: a. paraventricular nucleus. b. ventromedial hypothalamus. c. arcuate nucleus. d. lateral preoptic area.

Q: An increase in the size of meals is most likely to occur following damage to which area of the hypothalamus? a. Paraventricular b. Lateral c. Preoptic d. Ventromedial

Q: Which area of the hypothalamus seems to be critical for the ending of meals? a. lateral hypothalamus b. ventromedial hypothalamus c. preoptic area d. paraventricular nucleus

Q: Rats with damage to the paraventricular nucleus (PVN) eat ____ compared to normal rats. a. larger meals b. more frequent meals c. more if the food tastes good and less if it tastes bad d. smaller meals

Q: Many kinds of information impinge onto two kinds of cells in one nucleus of the hypothalamus, which is regarded as the "master area" for control of appetite. That area is the: A suprachiasmatic nucleus. B sexually dimorphic nucleus. C solitary nucleus D arcuate nucleus

Q: High levels of leptin are associated with: a. decreased activity and eating. b. increased activity and eating. c. decreased activity and increased eating. d. increased activity and decreased eating.

Q: Leptin is produced by: a. the paraventricular nucleus. b. body fat. c. neuropeptide Y. d. orexin A.

Q: Fat cells produce: a. CCK. b. insulin. c. neuropeptide Y. d. leptin.

Q: ____ signals the brain about the body's fat reserves, providing a long-term indicator of whether meals have been too large or too small. a. Renin b. Insulin c. Leptin d. Glucagon

Q: Which of the following groups of people would most likely benefit from taking leptin? a. anorexic patients b. normal obese people c. obese people with faulty leptin receptors d. obese people who fail to produce leptin

Q: For most obese individuals, giving them leptin would: A decrease appetite. B increase appetite. C increase sensitivity to leptin. D produce little effect.

Q: Variations in insulin level alter hunger by changing the: a. rate of emptying by the stomach. b. availability of glucose to the cells. c. sensitivity of the taste buds. d. ability of CCK to cross the blood-brain barrier.

Q: Why do both high levels and very low levels of insulin lead to increased eating? a. Glucose leaves the blood to be stored as fat. b. Fat supplies are being rapidly converted to glucose. c. Little glucose is reaching the cells to be used as fuel. d. Activity of the taste buds is directly enhanced.

Q: Through what mechanism does insulin affect appetite? A It enables stored nutrients to enter the blood stream. B It enables glucose in the blood stream to enter the cells. C It converts other nutrients into glucose. D It converts glucose into other nutrients.

Q: What happens when blood levels of insulin are extremely low? a. Glucose leaves the blood to be stored as fat. b. Appetite is low. c. There is excess glucose in the blood, but it cannot enter the cells. d. The brain shifts to proteins as its main source of fuel.

Q: What insulin levels would we expect to find when an animal is putting on extra fat in preparation for migration or hibernation? a. very low, as in diabetes b. normal c. high d. unstable and rapidly fluctuating

Q: Chronically high insulin levels lead to increased appetite by: a. lowering body temperature, increasing the need for nutrition. b. preventing glucose from entering the cells. c. causing a high percentage of available glucose to be stored as fat. d. directly altering the responses of the taste buds.

Q: What happens when insulin levels are high upon completing a meal? a. Fat supplies are converted to glucose which enters the blood. b. Glucose entry into the cells decreases. c. Blood glucose levels increase. d. The individual feels hungry again soon after the meal.

Q: What happens when insulin levels are high? a. Fat supplies are converted to glucose, which enters the blood. b. Fat supplies are depleted. c. Glucose entry into the cells increases. d. The sphincter muscle between the stomach and the duodenum opens.

Q: Glucagon stimulates the liver to: a. convert glucose to glycogen. b. store glucose. c. convert glycogen to glucose. d. decrease blood glucose levels.

Q: Glucagon stimulates the liver to covert ____ to ____. a. glucose; glycogen b. glucose; insulin c. glycogen; glucose d. insulin; glycogen

Q: Which hormonal levels fluctuate when people are eating, or getting ready to eat? a. insulin levels fall b. insulin levels rise c. CCK levels rise d. CCK levels fall

Q: Which hormone controls the rate at which glucose leaves the blood and enters the cells? a. CCK b. Aldosterone c. Glucagon d. Insulin

Q: Why does the level of glucose in the blood vary so little under normal circumstances? a. Manufacturing glucose is a lengthy process, so the body uses it slowly. b. Glucose does not leave the blood to enter the cells of the body. c. Mammals learn to eat only foods that contain glucose. d. The liver can convert stored nutrients into glucose.

Q: The blood's glucose level ordinarily remains relatively constant because of the activity of: a. CCK. b. the liver. c. the thyroid gland. d. the gall bladder.

Q: Which of the following is NOT true about the hormone CCK (cholecystokinin)? a. The duodenum releases CCK when food distends the duodenum. b. CCK tightens the sphincter muscle between the stomach and duodenum. c. CCK crosses the blood-brain barrier and inhibits cells in the hypothalamus. d. CCK stimulates the vagus nerve and causes cells in the hypothalamus to release CCK as a neurotransmitter.

Q: One interpretation of how the hormone CCK promotes satiety is that it: a. speeds up the digestive processes in the intestines. b. increases the rate at which glucose enters the cells of the body. c. causes the stomach to fill more quickly. d. facilitates the emptying of the stomach.

Q: An injection of CCK will: a. increase sodium preferences. b. lead to a preference for fatty foods. c. decrease the size of the next meal. d. cause increased storage of food as fats.

Q: One way by which food in the duodenum inhibits appetite is by: a. inhibiting the release of CCK. b. releasing CCK. c. breaking down CCK into inactive components. d. releasing glucagon.

Q: When food distends the duodenum, the duodenum releases which hormone? a. Prolactin b. Aldosterone c. angiotensin II d. Cholecystokinin

Q: When food distends the duodenum, the duodenum releases which hormone? a. CCK b. Aldosterone c. angiotensin II d. Prolactin

Q: The splanchnic nerves convey information about: a. the nutrient contents of the stomach. b. discomfort in the stomach. c. satiety. d. thirst.

Q: If the duodenum is partly distended and the stomach is not full, rats will: a. continue to eat. b. eat larger meals. c. stop eating. d. drink more.

Q: The first digestive site that absorbs a significant amount of nutrients is the: a. mouth. b. stomach. c. duodenum. d. vagus.

Q: The vagus and splanchnic nerves help to control feeding by relaying information to the brain from the: a. taste buds. b. muscles. c. stomach. d. liver.

Q: The vagus nerve is to ____ as the splanchnic nerves are to ____. a. stomach fullness; nutrient contents of the stomach b. the taste of food; the texture of food c. nutrient contents of the stomach; water contents of the stomach d. oral factors (such as chewing and taste); stomach fullness

Q: By what means does the brain find out about the nutrient content of food in the stomach? a. Hormones b. activity of the vagus nerve c. activity of the splanchnic nerves d. the duodenum

Q: The brain finds out about the degree of stretch of the stomach from: a. visual feedback. b. the hormone angiotensin. c. sensory receptors on the skin of the abdomen. d. activity of the vagus nerve.

Q: In sham-feeding, animals are: a. allowed to chew but not swallow. b. allowed to chew and swallow, but the food never enters the stomach. c. only allowed to eat a mixture devoid of nutrients. d. only allowed to eat an artificial substance.

Q: Ordinarily, which of the following is the most important mechanism for ending a meal? A the amount of glucose in the blood B the amount of leptin reaching the brain C the amount of insulin reaching the brain D sensations from the stomach

Q: Taste and other mouth sensations contribute to: a. hunger. b. satiety. c. thirst. d. overeating.

Q: Tryptophan enters the brain by an active-transport protein that it shares with ____ and other large amino acids. a. phenylalanine b. melatonin c. lactose d. glucose

Q: Increasing tryptophan helps the brain produce ____, which induces sleepiness. a. glucose b. phenylalanine c. melatonin d. lactose

Q: A common misconception is that eating turkey increases the body's supply of ____, which enables the brain to make chemicals that make you sleepy. a. lactase b. tryptophan c. lacrose d. sucrose

Q: Many people, including physicians, believe that eating ____ makes children hyperactive. a. salt b. fatty foods c. sugar d. protein

Q: The ability to digest lactose varies in a patchy way from place to place on which continent? a. Asia b. Europe c. Africa d. Antarctica

Q: People who are lactose intolerant can consume a little milk, and larger amounts of ____, which are easier to digest. a. cheese and yogurt b. Meats c. fruits and vegetables d. beans

Q: Humans are a partial exception to which rule? a. Adults can all drink milk. b. They all have a declining level of lactose tolerance as they age. c. All children limit dairy products. d. Milk causes stomach cramps in all humans.

Q: What best explains the absence of the use of dairy products in many Asian cuisines? a. cultural bias b. digestive limitations c. religious taboos d. the geographic region's incapability of supporting dairy animals

Q: After a certain age, most mammals lose their ability to metabolize lactose because: a. levels of the enzyme lactase decline. b. it competes with other nutrients in other food types. c. eating meat is not compatible with drinking milk. d. they no longer need the nutrients found in milk.

Q: Most young mammals stop nursing, at least partly, due to the loss of what ability? a. metabolizing the sugar in milk b. sucking sufficiently c. the Babinski reflex d. digesting the fat in milk

Q: The large intestine: a. absorbs water and minerals. b. digests proteins, fats, and carbohydrates. c. is the main site for the absorption of digested foodstuffs into the bloodstream. d. stores excess nutrients as glycogen, protein, or fat.

Q: The small intestine: a. absorbs water and minerals. b. digests proteins, fats, and carbohydrates. c. is the secondary site for the absorption of digested foodstuffs into the bloodstream. d. stores excess nutrients as glycogen, protein, or fat.

Q: What is the main site for absorption of digested food into the bloodstream? a. Esophagus b. Stomach c. Small intestine d. Large intestine

Q: The esophagus brings food from the: a. mouth to the stomach. b. stomach to the sphincter. c. sphincter to the intestines. d. stomach to the intestines.

Q: What is the first point in the digestive system where enzymes begin to break down food? a. Mouth b. Esophagus c. Stomach d. small intestine

Q: Small birds generally eat: a. as much as they can at one time. b. only what they need at the moment. c. three discrete meals per day. d. mostly during the night.

Q: Bears eat as much as they can at one time because: a. they do not regulate body temperature. b. they do not need a constant supply of energy. c. their main foods are available in large quantities for short times. d. their food is always difficult to find.

Q: A combination of the hormones aldosterone and angiotensin II leads to an increase in preference for ____ tastes. a. sweet b. sour c. salty d. bitter

Q: Aldosterone and angiotensin II together change the properties of ____, neurons in the nucleus of the tractus solitarius. a. renin receptors b. sodium receptors c. smell receptors d. taste receptors

Q: Aldosterone triggers: a. conservation of water. b. an increased preference for salty tastes. c. excretion of sodium. d. a decreased preference for salty tastes.

Q: The hormone aldosterone results in the: a. conservation of water. b. excretion of sodium. c. conservation of sodium. d. decreased preference for salty tastes.

Q: Strong craving for salty tastes is known as: a. potassium-specific thirst. b. sodium-specific hunger. c. sodium-specific thirst. d. potassium-specific hunger.

Q: What effect does the hormone angiotensin II have? a. increased storage of food as fat b. constriction of blood vessels c. decreased emptying of the stomach d. increased growth of the gonads

Q: The effect of an injection of a drug that blocks angiotensin II receptors would be: a. decreased hunger. b. decreased drinking. c. increased drinking. d. increased blood pressure.

Q: Hypovolemia induces thirst by inducing production of which hormone? a. CCK b. Insulin c. Prolactin d. Angiotensin II

Q: Severe blood loss will result in a preference for: a. pure water. b. slightly salty water. c. highly concentrated salt solutions. d. carbohydrates.

Q: Individuals who have lost sodium and other solutes: a. may experience a craving for salty tastes. b. must learn by trial and error to replace the correct amount. c. will often experience a craving for vitamins. d. lose ability to discriminate among tastes.

Q: Hypovolemic thirst: a. depends mostly on the lateral preoptic area. b. can be satisfied better by salt water than by pure water. c. is stimulated by an increased concentration of solutes in the blood. d. can only be satisfied by drinking a great deal of pure water.

Q: Vasopressin and angiotensin II are similar in that they both promote: a. increased urination. b. decreased thirst. c. decreased blood pressure. d. increased blood pressure.

Q: Sodium-specific hunger is closely associated with: a. osmotic thirst. b. hypovolemic thirst. c. the OVLT. d. decreased renin release.

Q: An animal with hypovolemic thirst will drink: a. a large volume of pure water. b. only enough to moisten its throat. c. mildly salty water rather than pure water. d. only water with a low pH.

Q: Consuming too much salt will trigger ____ thirst. Bleeding or heavy sweating will trigger ____ thirst. a. sympathetic, parasympathetic b. parasympathetic, sympathetic c. osmotic, hypovolemic d. hypovolemic, osmotic

Q: After a loss of blood volume, an animal will: a. drink whatever it can find, indiscriminately. b. drink a great deal of pure water. c. drink excessively concentrated saltwater. d. alternately drink pure water and excessively concentrated saltwater.

Q: Like vasopressin, ____ constricts the blood vessels, compensating for the drop in blood pressure. a. angiotensin I b. angiotensin II c. renin d. sodium

Q: A loss of blood will lead to what kind of thirst? a. Osmotic b. Non-homeostatic c. Hypovolemic d. Postprandial

Q: What causes hypovolemic thirst? a. dryness of the throat b. low blood volume c. increased concentration of solutes in the blood d. too much salt in the diet

Q: The lateral preoptic area and surrounding parts of the hypothalamus control: a. CCK levels. b. hunger. c. drinking. d. vasopressin levels.

Q: A rat with damage to its lateral preoptic area: a. drinks a lot of water. b. drinks only to wash down its food. c. has normal osmotic thirst but impaired hypovolemic thirst. d. has impaired osmotic thirst.

Q: The rate at which the posterior pituitary releases vasopressin is under the control of the: a. lateral preoptic area of the hypothalamus. b. supraoptic and paraventricular nuclei. c. subfornical organ. d. thalamus.