Deck 17: Energy Balance and Temperature Regulation

Question 1

The factor that increases the metabolic rate to the greatest extent is increased

A)skeletal muscle activity
B)mental effort
C)dietary fiber intake
D)epinephrine secretion
E)brown fat deposition

Answer 1

A

Question 2

The lowest metabolic rate occurs

A)during sleep
B)during a basal metabolic rate determination
C)during exercise
D)after a meal
E)in males compared to females

Answer 2

A

Question 3

Internal work includes

A)all of the energy-expending activities that must go on all of the time to sustain life
B)all energy expenditure by tissues other than skeletal muscles
C)the energy expenditure required to move external objects
D)both a and b
E)all of the above

Answer 3

A

Question 4

The energy equivalent of O₂ is

A)4.8 kilocalories of energy liberated per liter of O₂ consumed
B)used to indirectly measure the metabolic rate
C)the energy required to raise 1 gm of H2O 1◦C
D)both a and b
E)all of the above

Question 5

When a negative energy balance exists,

A)the body must make use of stored energy reserves
B)the caloric content of the food ingested is less than the energy output
C)the caloric content of the food ingested exceeds the energy lost due to heat or work
D)energy has been destroyed by catabolic processes within the body
E)both a and b are true

Question 6

If more energy is contained in the food eaten than is expended, then

A)a positive energy balance will exist
B)the excess energy will be stored in adipose
C)all of the excess energy will be liberated
D)a and b are true
E)a and c are true

Question 7

Energy required _____________ is not internal work?

A)for active transport
B)to pump blood
C)to move the body in relation to the environment
D)during synthetic reactions
E)to maintain body posture

Question 8

Select the hormone that is an important satiety signal.

A)ADH
B)Leptin
C)Glucagon
D)Glucose
E)TSH

Question 9

____ increases metabolic rate.

A)Exercise
B)Diet-induced thermogenesis
C)Epinephrine
D)Thyroid hormone
E)All of the above

Question 10

____ percent of the energy found in nutrient molecules is lost as heat.

A)10
B)25
C)50
D)75
E)90

Question 11

There are approximately ____ kilocalories of energy liberated per ____ of O₂ consumed.

A)3.8; milliliter
B)4.8; 10 liters
C)4.8; liter
D)4.0; 100 milliliters
E)both 3.8; milliliter and 4.8; liter

Question 12

Which statement is incorrect?

A)There are a pair of feeding centers and a pair of satiety centers in the hypothalamus that play a major role in controlling food intake.
B)Stimulation of the feeding centers drives the individual to eat.
C)Stimulation of the satiety centers brings about the feeling of having had enough to eat.
D)Distention of the stomach does not decrease appetite.
E)Destruction of the satiety center in lab animals leads to overeating and obesity.

Question 13

Which of the following is not a requirement for measurement of the basal metabolic rate (BMR)?

A)The person must not have exercised for at least 30 minutes.
B)The person must not have eaten any food within 12 hours.
C)The person must have slept at least seven hours the previous night.
D)The person should be at mental rest during the measurement.
E)The measurement should take place at a comfortable room temperature.

Question 14

_________ does not act as a satiety signal?

A)Cholecystokinin
B)Increased glucose utilization
C)Orexin
D)Leptin
E)Insulin

Question 15

The energy equivalent of oxygen is

A)the number of calories contained in every liter of oxygen consumed
B)the amount of energy is liberated from food for every liter of oxygen consumed
C)the amount of oxygen required for the processing and storage of ingested foodstuff
D)the energy required to raise 1 g of H2O 1◦C
E)none of the above

Question 16

If a young woman consumes 1,200 ml of O₂ in a six-minute basal metabolic rate test period, her BMR is

A)72 kcal/hour
B)57.6 kcal/hour
C)12 kcal/hour
D)4 kcal/hour
E)none of these

Question 17

The satiety center is located in the ____ of the brain.

A)cerebellum
B)cerebrum
C)hypothalamus
D)medulla
E)thalamus

Question 18

Only about ____ percent of the energy found in nutrient molecules is transferred to ATP.

A)10
B)25
C)50
D)75
E)90

Question 19

Leptin

A)is secreted by adipocytes
B)leads to appetite suppression
C)targets the hypothalamus
D)is both a and c
E)is all of the above

Question 20

About ____ kilocalories of energy is liberated by consumption of three liters of oxygen.

A)4.8
B)9.6
C)14.4
D)19.2
E)24

Question 21

A person can lose heat to an environment warmer than the body by means of

A)radiation
B)evaporation
C)conduction
D)radiation and conduction
E)evaporation and conduction

Question 22

Most people suffer convulsions when internal body temperature reaches ____◦F.

A)96
B)98
C)100
D)102
E)106

Question 23

The type of heat loss that occurs by sitting on a cold car seat is

A)radiation
B)convection
C)conduction
D)evaporation
E)none of these

Question 24

On average, about half of the body heat that is lost is due to

A)radiation
B)convection
C)conduction
D)evaporation
E)none of these

Question 25

Which of the following is not a means of increasing or conserving heat production?

A)shivering
B)skin vasodilation
C)nonshivering thermogenesis
D)increased muscle tone
E)increased exercise

Question 26

The major means of decreasing heat loss in response to a cold environmental temperature is

A)skin vasoconstriction
B)skin vasodilation
C)increasing the temperature gradient between the skin and environment
D)formation of "goose bumps"
E)both a and d

Question 27

____ has a positive effect on appetite.

A)CCK
B)PYY3-36
C)Leptin
D)Insulin
E)Ghrelin

Question 28

Most people's core temperature varies by about ____◦F.

A)0.6
B)1.8
C)2.6
D)4.0
E)5.2

Question 29

Receptors that relay thermal information to the temperature control centers include

A)peripheral warm and cold thermoreceptors in the skin
B)central thermoreceptors in the hypothalamus
C)central thermoreceptors in internal organs
D)both a and c
E)all of the above

Question 30

When the surrounding temperature is low, heat is lost from the body by means of

A)radiation
B)conduction/convection
C)nonshivering thermogenesis
D)a and b
E)all of the above

Question 31

"Normal" body temperature may vary slightly as a result of

A)exercise
B)the menstrual cycle
C)the time of day
D)exposure to extremes in environmental temperature
E)all of the above

Question 32

The leading theory for maintenance of body weight as a result of long-term matching of food intake to energy expenditure relates to the

A)amount of fat stored in adipose tissue
B)extent of glucose utilization
C)magnitude of cellular ATP production
D)extent of gastrointestinal distention
E)extent of behavioral modification associated with eating habits

Question 33

The major means of increasing heat production in response to a cold environmental temperature is

A)skin vasoconstriction
B)wearing warm clothing
C)increased muscle activity, such as through shivering and increased voluntary exercise
D)formation of "goose bumps"
E)increased food intake

Question 34

Sweating is

A)an active evaporative heat-loss process under sympathetic nervous control
B)the only means of losing heat when the environmental temperature is warmer than body temperature
C)the only means by which evaporative heat loss can take place in the body
D)a and b
E)all of the above

Question 35

Core temperature is

A)normally maintained relatively constant around 100◦F
B)the temperature of the abdominal and thoracic organs, the central nervous system, and the skeletal muscles
C)the temperature of the skin and subcutaneous fat
D)both a and b
E)both a and c

Question 36

Radiation

A)refers to heat emission from a warm object in the form of electromagnetic waves
B)is only source of heat loss for the body; i.e., you can lose but not gain heat by radiation
C)refers to the transfer of heat by direct contact between a warmer and cooler object
D)involves the continued cycling of cool air over the body
E)refers to the transformation of water from a gaseous to a liquid state

Question 37

Each of the following is a means of generating or holding heat in the body except

A)diminished sweating
B)exercising
C)shivering
D)vasodilation in the skin
E)behavioral adaptations

Question 38

Radiation and conduction are two types of heat exchange between the body and environment.The magnitude of heat loss via these two processes is determined by the

A)amount of sweating
B)temperature difference between body surface and its surroundings
C)absolute core temperature
D)extent of evaporation from the body surface
E)distance between the two objects that are exchanging heat

Question 39

Heat can be lost directly to the external environment by the vasodilation of blood vessels in the ____.

A)hypothalamus
B)cerebellum
C)skin
D)cerebral cortex
E)medulla

Question 40

Sweating

A)causes vasodilation of the skin vessels
B)increases the insulative capacity of the skin so that less heat can be gained from the environment
C)is the only heat-loss mechanism available to the body when the environmental temperature is so high that a normal temperature gradient between the skin and the environment cannot be established
D)both a and b
E)both b and c

Question 41

When vasodilation of the blood vessels in the skin occurs, then

A)the skin temperature becomes warmer than the core temperature
B)the insulative capacity of the skin is increased
C)heat will be lost from the body if the air temperature is cooler than skin temperature
D)b and c are true
E)all of the above are true

Question 42

Which substance decreases appetite?

A)Neuropeptide Y
B)Orexin
C)Ghrelin
D)Melanocortin
E)None of the above

Question 43

Vasoconstriction of blood vessels in the skin

A)is coordinated by the sympathetic nervous system
B)increases heat exchange with the environment
C)occurs when core body temperature is elevated
D)is both a and b
E)is both b and c

Question 44

_________ does not characterize heat exhaustion.

A)Reduced plasma volume
B)Extensive sweating
C)Rapidly rising body temperature
D)Fainting
E)Reduced blood pressure

Question 45

Energy cannot be created or destroyed, but it can be transformed from one form of energy into another.

Question 46

________ does not occur upon exposure to cold.

A)Skin vasoconstriction
B)Decreased muscle tone
C)Nonshivering thermogenesis
D)Behavioral adaptations
E)Stimulation of thermoreceptors

Question 47

A fever develops when

A)endogenous pyrogen released from neurons of the cerebral cortex in response to an infection elevates the hypothalamic "set point"
B)cold response mechanisms are initiated by the hypothalamus to raise the body temperature to the new set point
C)heat loss mechanisms are triggered to eliminate the excess heat from the body
D)a and b occur
E)a and c occur

Question 48

Which of the following activities has the largest energy expenditure in 5 minutes?

A)jogging
B)bicycling
C)walking up stairs
D)shoveling snow
E)walking slowly on level ground

Question 49

_________ release endogenous pyrogens in the body.

A)Muscle cells
B)Pathogens
C)Platelets
D)Erythrocytes
E)Macrophages

Question 50

A current is most closely associated with

A)convection
B)conduction
C)evaporation
D)radiation
E)heat waves

Question 51

Which statement is correct?

A)In a cold environment, the body gains heat by conduction, convection, radiation, and evaporation.
B)In a hot environment when the temperature of the environment exceeds that of the skin surface, convection is the only means for the body to lose heat.
C)Temperature control centers in the hypothalamus receive input from peripheral thermoreceptors in the skin and central thermoreceptors in the hypothalamus and internal organs.
D)All of the above
E)Only b and c

Question 52

The temperature control center within the anterior region of the hypothalamus is activated by ______ and initiates reflexes that mediate ______.

A)cold; heat production and heat conservation
B)cold; heat loss
C)warmth; heat loss
D)warmth; heat production and heat conservation
E)warmth; vasoconstriction

Question 53

The thermoneutral zone is

A)maintained by sweating and shivering mechanisms
B)the temperature within the body core that remains constant despite changes in environmental temperature
C)the environmental temperature range within which core temperature can be kept constant by skin vasomotor responses without calling supplementary heat-production or heat-loss mechanisms into play
D)the controlled environment within a building equipped with both heating and air-conditioning
E)the environmental temperature identical to core temperature so that body temperature is held constant without any physiological compensatory mechanisms being instituted

Question 54

Thermogenin is

A)found in certain mitochondria
B)found in brown fat
C)an uncoupling protein
D)disconnects the electron transport system from ATP synthesis
E)all of the above

Question 55

Which pairing is most out of place with reference to thermoregulation?

A)Increased muscle tone, vasoconstriction
B)Decreased voluntary exercise, nonshivering thermogenesis
C)Vasodilation, sweating
D)Shivering, vasoconstriction
E)Decreased muscle tone, cool clothing

Question 56

The development of fever

A)results from resetting of the medullary thermoregulatory center
B)may develop when mast cells release pyrogens
C)is mediated by prostaglandins
D)is both a and b
E)is all of the above

Question 57

Identify the correct statement(s):

A)Heat generation decreases after a person eats a meal.
B)Four calories are released for every gram of glucose oxidized.
C)In general, 4.8 calories (not Kcal) are liberated for every milliliter of O₂ consumed
D)Thyroid hormone is not the primary determinant of BMR.
E)Both a and b

Question 58

_______ is/are the means of heat energy emission from the surface of a warm body.

A)Radiation
B)Conduction/convection
C)Evaporation
D)Radiation and evaporation
E)All of the above

Question 59

Which of the following mechanisms help to maintain body temperature on hot days?

A)Decreased muscle tone
B)Skin vasodilation
C)Sweating
D)Only two of these
E)a, b, and c

Question 60

Nonshivering thermogenesis is

A)stimulated by epinephrine and thyroid hormone
B)the general increase in muscle tone in response to abrupt exposure to cold
C)increasing the insulative capacity of the skin by promoting increased deposition of brown fat under the skin
D)the elevation of body temperature in response to pyrogen release
E)none of the above

Question 61

Leptin is a hormone released from adipose tissue.

Question 62

Oral temperature is lower than the core temperature.

Question 63

The most dominant factor influencing the BMR is the level of circulating, active thyroid hormone.

Question 64

Neuropeptide Y is a strong appetite inhibitor.

Question 65

Internal work includes the expended energy when skeletal muscles are contracted to move external objects.

Question 66

There is an obligatory increase in metabolic rate resulting from food intake.

Question 67

Most of the energy contained within food will be lost as heat.

Question 68

The appetite centers stimulate feeding behavior, whereas the satiety centers inhibit feeding behavior.

Question 69

Metabolic rate equals energy expenditure/unit of time.

Question 70

Weight loss occurs when the energy derived from the food consumed is less than the energy expended by the body.

Question 71

The feeding and satiety centers are located in the hypothalamus.

Question 72

Overweight people tend to eat more on a daily basis than thinner people do.

Question 73

An animal can be driven to overeat either by selective stimulation of the appetite centers or by destruction of the satiety centers.

Question 74

Leptin stimulates the release of melanocortins.

Question 75

Metabolic rate can be measured indirectly by measuring the rate of oxygen consumption.

Question 76

Psychosocial influences can lead to obesity.

Question 77

The basal metabolic rate is the body's lowest metabolic rate.

Question 78

The core temperature is maintained at a near constant level, but skin temperature is quite variable.

Question 79

As the level of circulating, active thyroid hormone increases, the BMR increases correspondingly.

Question 80

A decrease of insulin in the blood may signal satiety.