Deck 9: Homeostasis, Motivation, and Reward

Question 1

 Jessica's weight of 123 pounds doesn't vary much regardless of what she eats from day to day. It is likely that 123 pounds is Jessica's

A) ideal weight.
B) set point.
C) homeostasis.
D) drive state.

Answer 1

set point.

Question 2

 Michael is determined to lose 50 pounds. In addition to looking and feeling great, what else should Michael expect?

A) His reactions to hot and cold weather will not change due to his weight loss.
B) He will feel warmer than before in hot weather.
C) He will feel warmer than before in cold weather.
D) He will feel cooler than he did before in both warm and cold weather.

Answer 2

He will feel cooler than he did before in both warm and cold weather.

Question 3

 An animal's surface-to-volume ratio predicts

A) that it is an ectoderm.
B) that it is an endoderm.
C) how much heat the animal can generate.
D) how much energy the animal requires to maintain core temperature.

Answer 3

how much energy the animal requires to maintain core temperature.

Question 4

 Based on surface-to-volume ratios, which of the following animals would require the most energy to maintain core temperature?

A) a mouse
B) a dog
C) a human
D) an elephant

Question 5

 Animals in cold climates have _________ surface area, thereby _________ heat loss.

A) less; minimizing
B) less; maximizing
C) greater; minimizing
D) greater; maximizing

Question 6

 Professor Rayfield is discussing body temperature and surface area to volume ratio. He tells the class that a _____ would have to work harder to maintain body heat.

A) horse
B) rat
C) human
D) whale

Question 7

 Shivering and blood vessel constriction

A) dissipate heat in ectotherms.
B) dissipate heat in endotherms.
C) generate and conserve heat in ectotherms.
D) generate and conserve heat in endotherms.

Question 8

 Animals that rely on external factors to maintain their core temperature, such as basking in the sunlight, are known as

A) endotherms.
B) ectotherms.
C) mesotherms
D) warm-blooded animals.

Question 9

 Animals with large body volumes generate _________ animals with small body volumes.

A) more heat than
B) less heat than
C) the same amount of heat as
D) more heat than some animals with small body volumes and less heat than other

Question 10

 Animals that maintain their core temperature through internal metabolic activity are known as

A) endotherms.
B) ectotherms.
C) mesotherms.
D) cold-blooded animals.

Question 11

 The process of activating and directing behavior designed toward a specific goal is known as

A) motivation.
B) homeostasis.
C) drive.
D) tension.

Question 12

 Anna has a pet bird named Tweety. Anna is an _____ and her bird is an_______.

A) endotherm; endotherm
B) endotherm; ectotherm
C) ectotherm; ectotherm
D) ectotherm; endotherm

Question 13

 A biologist is studying an animal with an elongated body and very long legs, ears, and tail. It is likely that this animal lives in a _________ climate.

A) cold
B) moderate
C) hot
D) dry

Question 14

 Eldon works in a zoo and his favorite animal is a rattlesnake named Viper. Viper is an ______ and often _____ to stay warm.

A) ectotherm; shivers
B) ectotherm; basks under a heat lamp
C) endotherm; shivers
D) endotherm; basks under a heat lamp

Question 15

 Which of the following occur in response to physiological deficits and disappear when needs are met?

A) set points
B) drive states
C) thermostats
D) states of equilibrium

Question 16

 A physiological state of equilibrium or balance is called

A) motivation.
B) a set point.
C) homeostasis.
D) drive.

Question 17

 The Walkers like to keep their home's thermostat set to 68 degrees F. This setting is analogous to a body's

A) motivation.
B) homeostasis.
C) set point.
D) drive state.

Question 18

Professor Arevalo is teaching her class about _____ and gives them the example that humans need to maintain a body temperature around 98.6 degrees.

A) set points
B) drive states
C) homeostasis
D) motivation

Question 19

 Warm-blooded and cold-blooded animals attempt to maintain

A) approximately the same internal temperatures but do so through different methods.
B) approximately the same internal temperatures using the same methods.
C) very different internal temperatures, with the warm-blooded animals having internal temperatures about 10°F higher than cold-blooded animals.
D) very different internal temperatures but use the same methods to maintain their respective set points.

Question 20

 A particular value defended by a regulatory system, such as body weight or core temperature, is known as

A) motivation.
B) a set point.
C) homeostasis.
D) drive.

Question 21

 Following open heart surgery or cardiac arrest, it has become common for physicians to

A) artificially produce a state of mild hyperthermia in a patient.
B) artificially produce a state of mild hypothermia in a patient.
C) increase the levels of pyrogens in the brain.
D) artificially produce a state of fever.

Question 22

 Temperature-insensitive neurons in the POA and posterior hypothalamus

A) play no role in the maintenance of core temperature.
B) increase their firing rate when temperature reaches a set point.
C) maintain a fairly steady firing rate.
D) increase their firing rate when core temperature increases.

Question 23

 Adrian is at risk for heat stroke because

A) he is wearing heavy clothing and engaging in strenuous activity.
B) his pyrogens were released by disease-causing organisms.
C) his genetic predispositions cause him to sweat too much.
D) he has been drinking large quantities of fluid.

Question 24

 Ashley has been diagnosed with a low thyroid condition. She frequently experiences

A) lower-than-normal core body temperatures.
B) unexplained fevers.
C) hyperthermia requiring hospitalization.
D) usually high activity in her brown fat cells.

Question 25

 Hypothermia occurs when a person's core body temperature

A) increases to 102°F.
B) increases to 104°F.
C) decreases below 98°F.
D) decreases below 95°F.

Question 26

 The preoptic area (POA) contains

A) no temperature-responsive neurons.
B) neurons that respond to any change in core temperature.
C) two types of neurons that respond to either increases or decreases in core temperature.
D) three types of neurons that respond to increases in temperature, decreases in temperature, or are temperature insensitive.

Question 27

 Artie has been diagnosed with Raynaud's disease. She has to be very careful when she

A) takes a shower in water that is too warm.
B) gets a fever.
C) takes hormone supplements, especially those containing estrogens.
D) gets items out of her deep freezer.

Question 28

 You have been hiking, and as night falls and the temperature drops, the first part of your temperature regulation system to be activated is probably your ________, which will trigger your _________ to make you shiver.

A) spinal cord; skin receptors
B) skin receptors; hypothalamus
C) brainstem; hypothalamus
D) hypothalamus; skin receptors

Question 29

 In comparison with white fat cells, brown fat cells appear

A) larger.
B) different due to their greater amounts of mitochondria.
C) the same and can be identified only by their location.
D) different due to their smaller amounts of mitochondria.

Question 30

 Temperature regulation is managed by a

A) single system in the hypothalamus.
B) single system in the spinal cord.
C) hierarchy of systems extending from the spinal cord to the hypothalamus.
D) hierarchy of systems extending from the medulla to the spinal cord.

Question 31

 Jenae is going through menopause and has been experiencing hot flashes because her _______ levels have _______.

A) estrogen; increased
B) estrogen; decreased
C) thyroid hormone; increased
D) thyroid hormone; decreased

Question 32

 In response to cold temperatures, an infant's _________ nervous system stimulates _________ fat activity.

A) parasympathetic; white
B) parasympathetic; brown
C) sympathetic; white
D) sympathetic; brown

Question 33

 Fevers due to illness

A) have no benefit and should be reduced immediately through the use of medication.
B) represent a failure of the body's temperature control system.
C) result from a resetting of the body's temperature set point.
D) occur when the body's set point is exceeded.

Question 34

 If for some reason your hypothalamus doesn't raise your core temperature when you are exposed to very cold temperatures,

A) you will die of hypothermia.
B) you will die of hyperthermia.
C) your brainstem and spinal cord will attempt to raise your core temperature.
D) your temporal lobe will tell you to move to a warmer environment, which will take care of the problem.

Question 35

 Deficits in thyroid functions often produce

A) fever.
B) higher than normal body temperatures.
C) lower than normal body temperatures.
D) inappropriate constriction of blood vessels.

Question 36

 During the summer heat, Bennett stays cool by

A) perspiring and dilating his blood vessels.
B) perspiring and constricting his blood vessels.
C) increasing his thyroid activity and reducing his brown fat cell numbers.
D) stimulating his brown fat activity and increasing his white fat cell numbers.

Question 37

 People with spinal cord damage

A) do not have any problems with temperature regulation, because the spinal cord is the most sensitive part of the temperature regulation system.
B) have problems regulating core temperature in cold but not hot conditions.
C) have problems regulating core temperature in hot but not cold conditions.
D) have difficulty regulating temperature, because the spinal cord temperature regulating systems are less precise than brainstem or hypothalamic systems.

Question 38

 Sensitivity to changes in temperature is

A) equally precise in all structures related to temperature regulation.
B) more precise in the brainstem than in the spinal cord or hypothalamus.
C) more precise in the spinal cord than in the hypothalamus.
D) more precise in the hypothalamus than in the spinal cord.

Question 39

 Core temperatures in humans

A) should be maintained within a range of 10 degrees in order for us to feel well.
B) are not as important as they are in animals that are ectotherms.
C) can vary quite a bit from person to person but must be maintained within a range of 10 degrees in order for us to feel well.
D) must be maintained within a very few degrees or life-threatening conditions can occur.

Question 40

 Risk for hyperthermia is increased when a

A) person has immune system problems.
B) woman is approaching menopause.
C) person has a low thyroid condition.
D) person is using antibiotics.

Question 41

 Blake is studying for a quiz and writes in his notes that the extracellular fluid in his body would include

A) fluid contained within his body cells.
B) his blood supply, cerebrospinal fluid, and interstitial fluid.
C) his cerebrospinal fluid and the fluid contained within his body cells.
D) his interstitial fluid and the fluid contained within his body cells.

Question 42

 Ronnie is most likely experiencing osmotic thirst because of

A) injuries leading to loss of blood.
B) reductions in blood pressure.
C) cellular dehydration.
D) decreases in the concentration of extracellular sodium.

Question 43

 Floria is most likely experiencing hypovolemic thirst because of

A) increases in blood pressure.
B) decreases in blood volume.
C) feelings of a dry mouth.
D) decreases in intracellular fluid levels.

Question 44

 An emergency room (ER) staff has been alerted by an ambulance of the imminent arrival of a patient who nearly drowned at a nearby beach. The ER staff should expect that the patient will have inhaled a large amount of seawater, and consequently will need to treat the patient for the effects of highly

A) hypotonic extracellular fluid, including possible cell rupture.
B) hypotonic extracellular fluid, including possible cell dehydration.
C) hypertonic extracellular fluid, including possible cell dehydration.
D) hypertonic intracellular fluid, including possible cell rupture.

Question 45

 The human blood supply makes up about _________ percent of the body's total fluids.

A) 2
B) 7
C) 13
D) 26

Question 46

 Most excess sodium and water in the body are excreted by

A) the intestines.
B) the kidneys.
C) perspiring.
D) respiration.

Question 47

 The "rule" that says humans should drink eight cups of plain water per day is

A) a good one, because that is about the right amount of fluids everybody needs.
B) not so good, because we need about twice that much fluid for good health and skin.
C) unnecessary, because we take in all the fluids we need from our foods.
D) unnecessary, because we take in about half the fluid we need from our foods.

Question 48

(see Figure 9.6)
Bernice is studying for a quiz. She writes in her notes that the structure labeled #1 is called the

 

A) posterior hypothalamus.
B) septal area.
C) pituitary gland.
D) POA of the hypothalamus.

Question 49

 Electrolytes are

A) substances that have broken up into ions in a solution.
B) solutes that do not carry an electrical charge.
C) positively charged solutes.
D) negatively charged solutes.

Question 50

 Humans need to ingest

A) no fluids in addition to those contained in food.
B) about 0.3 liters (about 0.10 gallons) of fluid per day.
C) about 1 liter (about 0.27 gallons) of fluid per day.
D) about 2.5 liters (about 0.55 gallons) of fluid per day.

Question 51

 Pyrogens influence fever by which of the following mechanisms of action?

A) inhibiting the activity of temperature-insensitive neurons
B) increasing the activity of cold-sensitive neurons
C) reducing the activity of warm-sensitive neurons
D) increasing the activity of warm-sensitive neurons

Question 52

 Intracellular fluid makes up about _________ of the body's total fluids.

A) one-tenth
B) one-third
C) two-thirds
D) three-quarters

Question 53

 Tennie is in her physiology lab and is working on a lab project. Her teacher hands out a syringe filled with an isotonic solution. The solution has

A) a higher concentration of solutes than normal body fluids.
B) a lower concentration of solutes than normal body fluids.
C) an equal concentration of solutes as normal body fluids.
D) the same solutes in the same concentrations as normal body fluids.

Question 54

 Stuart was in a serious automobile accident and, in addition to breaking several bones, he suffered a deep cut that was bleeding badly. As he waited for help to arrive, it is likely that Stuart was beginning to experience

A) hyponatremia.
B) strong osmotic thirst.
C) strong hypovolemic thirst.
D) both hyponatremia and hypovolemic thirst.

Question 55

 Simona is in the laboratory and is working with a solution that has a lower level of solutes than human blood. Relative to blood, her solution would be

A) hypotonic.
B) isotonic.
C) hypertonic.
D) osmotic.

Question 56

 Kimberlie's core temperature has increased. As a result,

A) all temperature-sensitive neurons in her POA will increase their firing rates.
B) all temperature-sensitive neurons in her POA will decrease their firing rates.
C) warm-sensitive neurons will increase their firing rates, while cold-sensitive and temperature-insensitive neurons will maintain a steady rate of firing.
D) warm-sensitive neurons will inhibit cold-sensitive neurons, while temperature-insensitive neurons will not change.

Question 57

 In osmosis

A) solutes move from areas of high concentration to areas of low concentration.
B) solutes move from areas of low concentration to areas of high concentration.
C) water moves from areas of low concentration of solutes to areas of high concentration of solutes.
D) water moves from areas of high concentration of solutes to areas of low concentration of solutes.

Question 58

 In addition to receiving input from thermoreceptors in the skin and spinal cord, warm-sensitive cells in the preoptic area (POA) of the hypothalamus

A) receive input from cold-sensitive but not temperature-insensitive neurons in the POA.
B) have receptors that sense temperature change in their vicinity.
C) receive input from both cold-insensitive and temperature-insensitive neurons in the POA.
D) receive input from temperature-insensitive but not cold-sensitive neurons in the POA.

Question 59

 Nathan is drinking a sports drink filled with electrolytes. Compared to water, his drink is

A) hypotonic.
B) hypertonic.
C) isotonic.
D) osmotic.

Question 60

 Which of the following factors contributes the least to feelings of thirst?

A) feelings of a dry mouth
B) a reduction in intracellular fluid levels
C) a reduction in extracellular fluid levels
D) an increase in the concentration of extracellular solutes

Question 61

 Professor Ocampo studies drinking behavior in rats. She has found that rats will begin drinking when

A) aldosterone reaches the OVLT.
B) aldosterone reaches the subfornical organ.
C) angiotensin II reaches the OVLT.
D) angiotensin II reaches the subfornical organ.

Question 62

 Aldosterone is released by the

A) kidneys.
B) anterior pituitary gland.
C) posterior pituitary gland.
D) adrenal glands.

Question 63

 Renin is released by the

A) pituitary glands in response to ADH.
B) kidneys in response to ADH.
C) pituitary glands in response to angiotensin II.
D) kidneys in response to angiotensin II.

Question 64

 Denisse's _______ released renin in order to _______.

A) kidneys; trigger the release of ADH
B) kidneys; convert angiotensinogen into angiotensin II
C) posterior pituitary gland; convert angiotensinogen into angiotensin II
D) posterior pituitary gland; trigger the release of ADH

Question 65

 Kyle's father loves to add salt to his food, but given the family's history of high blood pressure and stroke, he is trying to avoid this practice. Why is eating less salt important in controlling blood pressure?

A) Excess salt damages the kidneys, resulting in a buildup of fluids leading to high blood pressure.
B) The kidneys get accustomed to higher levels of salt, interfering with their ability to monitor fluid levels properly.
C) High levels of salt in the blood cause water to leave the cells, and the higher blood volume increases blood pressure.
D) Higher levels of salt intake stimulate overdrinking and the resulting higher blood volume leads to high blood pressure.

Question 66

 Researchers have identified the _________ as the most likely location of osmoreceptors.

A) POA of the hypothalamus
B) posterior hypothalamus
C) lateral hypothalamus
D) organum vasculosum of the lamina terminalis (OVLT)

Question 67

 Antidiuretic hormone (ADH) is released in response to

A) osmotic thirst only.
B) hypovolemic thirst only.
C) either osmotic or hypovolemic thirst.
D) release of renin.

Question 68

 The subfornical organ communicates directly with the

A) posterior pituitary.
B) lateral hypothalamus.
C) median preoptic nucleus of the hypothalamus.
D) zona incerta.

Question 69

 Baroreceptors are located in the

A) OVLT.
B) heart and kidneys.
C) medulla.
D) stomach and digestive tract.

Question 70

 The function of angiotensin II is to

A) constrict blood vessels and trigger the release of aldosterone.
B) constrict blood vessels and trigger the release of renin.
C) dilate blood vessels and trigger the release of aldosterone.
D) dilate blood vessels and trigger the release of renin.

Question 71

 Monica had a serious case of the flu, with lots of vomiting and diarrhea. When she called the Health Center for advice, a nurse told her to

A) drink as much plain water as possible.
B) drink sports drinks containing sodium instead of plain water.
C) avoid drinking anything until the vomiting and diarrhea stopped completely.
D) drink coffee or tea without cream or sugar.

Question 72

 Vomiting and diarrhea may be life threatening when _________ sodium levels lead to_________ blood pressure.

A) reduced; low
B) reduced; high
C) increased; low
D) increased; high

Question 73

 Osmoreceptors appear to

A) increase their rate of firing when placed in a hypertonic solution and decrease their rate of firing when placed in a hypotonic solution.
B) increase their rate of firing when placed in a hypotonic solution and decrease their rate of firing when placed in a hypertonic solution.
C) increase their rate of firing when blood pressure drops.
D) decrease their rate of firing when blood pressure drops.

Question 74

 When hypovolemia is experimentally induced in research animals, they usually show

A) avoidance of sodium.
B) a specific hunger for sodium.
C) lack of thirst.
D) a specific hunger for glucose.

Question 75

 Chris just ate some really salty snacks. He is now experiencing

A) osmotic thirst due to loss of intracellular fluid.
B) osmotic thirst due to loss of extracellular fluid.
C) hypovolemic thirst due to loss of intracellular fluid.
D) hypovolemic thirst due to loss of extracellular fluid.

Question 76

 (see Figure 9.12) Shanda is studying this diagram because she has a quiz on how the body responds to _______ tomorrow.

 

A) normal eating behavior
B) temperature
C) thirst
D) abnormal eating behavior

Question 77

 Extreme thirst may occur in cases of diabetes mellitus due to

A) low blood volume.
B) low concentrations of solutes in the blood.
C) high concentrations of solutes in the blood.
D) high blood volume.

Question 78

 Medications used to treat high blood pressure include _________ because they _________ blood volume.

A) antidiuretics; increase
B) antidiuretics; reduce
C) diuretics; increase
D) diuretics; reduce

Question 79

 Professor Wedell tells her class that baroreceptors are important because they measure

A) blood pressure.
B) intracellular fluid volume.
C) sodium levels in the blood.
D) interstitial fluid volume.

Question 80

 Aldosterone signals the kidneys to

A) retain sodium.
B) excrete sodium.
C) increase urine production.
D) decrease urine production.