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Flashcards in Midterm 4 Heat generation and energy balance Deck (118)
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1

What kind of process is catabolism?

an endogenic process while energy is released

a building process

proteins are formed from amino acids

polysaccharides are formed from fats

An endogenic process while energy is released

Burning fat or glucose as energy source

2

What kind of process is anabolism?

an endogenic process while energy is released

a building process which needs energy for synthesis

a chemical reaction while compounds are transformed without energetic change

amino acids are formed from proteins

a building process which needs energy for synthesis

For example using proteins to build muscles or fat on the body

3

Who introduced the law of conservation of energy?

H. A. Krebs
W. Harvey
A. L. Lavoisier and P. S. Laplace.
H. Starling

Lavoisier and Laplace

4

Which hormone is important during long term adaptation to the changes in the environmental temperature?

noepinephrine
thyroid hormones
growth hormone
epinephrin

Thyroid hormones

5

What is the most common reason for the increase of the metabolic rate?

milk production
nutrition of the fetus
increase of muscle work
sympathetic tone

Increase of muscle work

6

Which growing animal has the best feed utilization?

lactating cow
pig
beef cattle
laying hen

Laying hen

7

What is true for vital protein digestion?

the undigested defecated protein is subtracted from the fodder's protein content

the undigested defecated protein and the endogenous nitrogen in the faeces are subtracted from the fodder's protein content

it is independent of the quantity of endogenous nitrogen

it is the exact measurent of protein digestibility

The undigested defecated protein and the endogenous nitrogen in the faeces are subtracted from the fodder's protein content

8

How can the net protein utilization be measured?

during its measurement it is unnecessary to starve the animal

the endogenous nitrogen content of the faeces is subtracted from the virtual protein digestion

the urine nitrogen is subtracted from the ingested protein

the undigested defecated protein is subtracted from the fodder's protein content

The urine nitrogen is subtracted from the ingested protein

9

What information does the biological utilization give?

it states the reason of improper protein utilization

it gives information on how much is the real protein digestion

it gives information on how much of the given fodder is absorbed in the gut

it gives information on how much of the degraded and absorbed protein can take part the synthesis of the organism's new proteins

it gives information on how much of the degraded and absorbed protein can take part the synthesis of the organism's new proteins

10

How can energy, which is released during metabolism, be calculated?

Energy released = stored energy - heat - work

Energy released = work + stored energy - heat

Energy released = (internal work - external work) + stored energy + heat

Energy released = stored energy + heat + work

Energy released = stored energy + heat + work

11

What is the definition of one calorie?

1 calorie is defined as the amount of energy required to raise the temperature of one gram of water from 14.5 °C to 15.5 °C

1 calorie is defined as the amount of energy required to raise the temperature of one gram of water by one degree Celsius

1 calorie is defined as the amount of energy released by combustion of 1 g of foodstuff

Calorie is a general unit of measurement for heat, work, and energy

1 calorie is defined as the amount of energy required to raise the temperature of one gram of water from 14.5 °C to 15.5 °C

12

Which of the measuring units below is associated the quantity of heat?

Calorie
Joule
Kcal
°C

Joule

13

What is the combustion heat for nutrients?

the amount of heat produced by burning of 1 g protein

the amount of heat produced by burning of 1 g foodstuff

the amount of heat produced by burning of 1 g particular nutrient

the difference between the energy released in the bomb calorimeter and the in the body

The amount of heat produced by burning of 1g particular nutrient

14

How can you determine the total heat energy in the foodstuff?

By direct calorimetry
By indirect calorimetry
By calculation
By bomb calorimeter

By bomb calorimeter

15

What is the "Hess law"?

The amount of energy released by oxidation is independent of the intermediate steps

Oxidation of proteins releases the same amount energy in the body and in the bomb calorimeter

The oxidation has the same intermediate steps in the body and in the bomb calorimeter

The combustion heat of different nutrients depends on the intermediate steps

The combustion heat of different nutrients depends on the intermediate steps

16

What is gross energy (GE)?

The difference of metabolizable energy and heat produced in the body

The energy content of the foodstuff measure in bomb calorimeter

GE = combustion heat - energy in faeces

GE = combustion heat - energy in faeces - energy in urine

The energy content of the foodstuff measure in the bomb calorimeter

17

What is the real protein digestion?

the undigested defecated protein is subtracted from the protein content of the feed

the endogenous nitrogen content in the faeces is subtracted from the virtual protein digestion

during its determination it is unnecessary to starve the animal

the endogenous nitrogen content of the faeces and the urine nitrogen content are subtracted from the virtual protein digestion

the endogenous nitrogen content in the faeces is subtracted from the virtual protein digestion

18

What is the digestible energy (DE)?

The energy content of the foodstuff measured in bomb calorimeter

DE = combustion heat - energy in faeces - energy in urine

DE = combustion heat - energy in faeces

The difference of metabolizable energy and heat produced in the body

DE = combustion heat - energy in faeces

19

What is the metabolizable energy (ME)?

ME = net energy - energy in urine

The energy content of the foodstuff measure in bomb calorimeter

ME = combustion heat - energy in faeces

ME = DE - energy in urine - fermentation energy

ME = DE - energy in urine - fermentation energy

20

What is net energy (NE)?

NE = metabolizable energy - heat loss - specific dynamic action

NE = DE - energy in urine - fermentation energy

The energy content of the foodstuff measure in bomb calorimeter

NE = combustion heat - energy in faeces - energy in urine

NE = metabolizable energy - heat loss - specific dynamic action

21

In which species can the metabolizable energy be determined directly?

Ruminants
birds
carnivores
none of the above

Birds (they defecate and urinate at the same time through the cloaca)

22

Which forms of energy can cover the needs of vital processes or can be utilized for production?

Metabolizable energy
Digestible energy
Net energy
Gross energy

Net energy

23

What portion of the gross energy is lost with the urine?

20 %
10-60%
5-12%
3-5%

3-5%

24

How much energy is lost with 1 mol of uric acid?

1925 kJ
634 kJ
1254 kJ
135 kJ

1925 kJ

25

What portion of the metabolizable energy is converted into net energy during pregnancy?

70 %
20 %
30-40%
90 %

20%

26

What portion of the metabolizable energy can be used for vital processes?

30-40%
90 %
70 %
20 %

70%

27

What is the basal metabolic rate?

The energy which is used to maintain constant body temperature

The energy which is used for vital processes

The energy production measured in standstill stage

The energy production measured in resting stage

The energy production measured in resting stage

28

What criteria determine the basal metabolic rate?

Complete resting, lying posture, absence of any psychic excitement, and neutral environmental temperature

natural environmental temperature, lying posture or having a rest, before morning feeding

standing posture, absence of any psychic excitement, and neutral environmental
temperature

Complete rest, standing posture, fasting

Complete resting, lying posture, absence of any psychic excitement, and neutral environmental temperature

Very hard to measure on animals

29

What criteria determine the resting metabolic rate?

Complete rest, lying posture, fasting, neutral environmental temperature

lying posture or having a rest, before morning feeding

can be measure only in humans, before food uptake, in absence of any psychic excitement

the specific dynamic action and the production energy have to be subtracted from the basal metabolic rate

Lying posture or having a rest, before morning feeding

30

What is the metabolic spectrum?

The energy turnover that is independent of the activity and production

Metabolic rate above the resting metabolic rate, which can be determined by measuring the oxygen consumption

Energy turnover above the basal metabolic rate (or resting metabolic rate)

Energy turnover which can be up to 100 folds of basal metabolic rate

Energy turnover above the basal metabolic rate (or resting metabolic rate)

31

Which statement is true for the Lavoisier's calorimetry?

The advantage is that it can be used on physically active animals

The water evaporated is absorbed by either H2SO4 or NaCO3

Water of known temperature is circulated in a copper tube in the heat isolated chamber; water is warmed up by the animal

The chamber, containing the animal, was surrounded by ice; the amounts of melted ice and the water being produced, were used for the estimation of heat generation

The chamber, containing the animal, was surrounded by ice; the amounts of melted ice and the water being produced, were used for the estimation of heat generation

32

How much energy is needed to melt 1 g of ice?

0.334 kJ
0.334 kcal
0.585 kcal
0.585 kJ

0.334 kJ

33

Which statement is true for the complex direct calorimetry?

The disadvantage is that it cannot be used on physically active animals

Water of known temperature is circulated in a copper tube in the heat- isolated chamber; water is warmed up by the animal

The chamber, containing the animal, was surrounded by ice; the amounts of melted ice and the water being produced, were used for the estimation of heat generation

Produced heat can be calculated by the energy which is needed to melt the ice

Water of known temperature is circulated in a copper tube in the heat-isolated chamber; water is warmed up by the animal

34

Which statement is true for the compensation calorimetry?

Water of known temperature is circulated in a copper tube in the heat- isolated chamber; water is warmed up by the animal

A double-walled chamber, the inner wall of which is a good conductor of heat, and the outer wall of which is kept under constant temperature.

The amount of heat dissipated through the wall of the chamber is measured in a way that the heat-difference

There are two chambers with identical thermal capacity, connected together and placed in a space with constant temperature; one of them contains the animal, the other a lamp

Measures the heat which is lost by radiation, conduction, and convection

There are two chambers with identical thermal capacity, connected together and placed in a space with constant temperature; one of them contains the animal, the other a lamp

35

Which statement is true for the gradient calorimetry?
Its disadvantage that it is complicated and not accurate
Measures only the heat which is lost by conduction
There are two chambers with identical thermal capacity, connected together and placed in a space with constant temperature; one of them contains the animal, the other a lamp
A double-walled chamber, the inner wall of which is a good conductor of heat, and the outer wall of which is kept under constant temperature. The amount of heat dissipated through the wall of the chamber is measured in a way that the heat- difference

4?

36

Why is the indirect calorimetry applied to monitor the energy balance?

More than 95% of energy utilized by the body is originated from the chemical reaction between oxygen and foodstuffs therefore the O2 is a reliable marker for energy turnover

Oxygen consumption gives information about the quality of food

The O2 is a reliable marker for energy turnover even during heavy physical activity

During combustion of 1 litre of oxygen, 20.18 J (4.825 cal) of energy is released

More than 95% of energy utilized by the body is originated from the chemical reaction between oxygen and foodstuffs therefore the O2 is a reliable marker for energy turnover

37

What is oxygen equivalency?

During combustion of 1 mol of oxygen, 1 mol of CO2 is released

During combustion of 1 litre of oxygen, 20.18 kJ (4.825 kcal) of energy is released

Combustion of 1 g fat requires the same amount of oxygen as 1 g carbohydrate

During combustion of 1 litre of oxygen, 20.18 J (4.825 cal) of energy is released

During combustion of 1 litre of oxygen, 20.18 kJ (4.825 kcal) of energy is released

38

What is the advantage of indirect calorimetry?

The O2 is a reliable marker for energy turnover even during heavy physical activity

Oxygen consumption gives information about the quality of the food

the animal can stay in its natural environment, it can move freely

there are no separate open and closed systems

the animal can stay in its natural environment, it can move freely

39

What is the disadvantage of indirect calorimetry?

During combustion of 1 litre of oxygen releases different amount of energy depending on the food quality

It is difficult to apply, the method is slow

The animal has to stay inside the laboratory

The method measures only O2- dependent energy production

The method measures only O2- dependent energy production

40

Which is the normal setup for open- system indirect calorimetry?

The amount and composition in the expired air is measured

The amount and CO2 content in the inspired air is measured

The amount and CO2 content in the expired air is measured

The amount and composition in the inspired air is measured

The amount and composition in the expired air is measured

41

What instrument is an open-system indirect calorimeter?

Krogh's device
Douglas bag
Knipping device
Haldane calorimeter

Douglas bag

42

Which is the normal setup for closed- system indirect calorimetry?

The amount and CO2 content of the expired air is measured and the oxygen consumption is deduced

The animal inspires from a closed bag and expires to the outside air

The animal is completely isolated from the outside air

The animal inspires from the outside air and expires into a closed bag

The animal is completely isolated from the outside air

43

What is the setup of the Krogh's device?

Expired CO2 can be measured by absorbing it with KOH

The oxygen used up is replenished and the volume measured

The device gives the possibility to measure both the oxygen consumption and the CO2 production

Oxygen is added previously to the system, then the amount of consumed oxygen is measured

Oxygen is added previously to the system, then the amount of consumed oxygen is measured

44

What is the respiratory quotient?

the volume of carbon dioxide produced divided by the volume oxygen consumed during the same time period

the volume of carbon dioxide produced minus the volume oxygen consumed during the same time period

the volume of carbon dioxide expired divided by the volume oxygen inspired during the same time period

gives information about the amount of fat, protein, and carbohydrate utilized

the volume of carbon dioxide produced divided by the volume oxygen consumed during the same time period

45

Combustion of which nutrient gives the most energy while using up 1 liter of oxygen?

Protein

Carbohydrate

Fat

the energy released is the same for all three nutrients above

Carbohydrates

46

What is the normal range of RQ?

0-1
0-10
0.7-1.0
0.5-0.7

0.7-1.0

47

What is RQ?

The respiratory quotient (or RQ or respiratory coefficient), is a dimensionless number used in calculations of basal metabolic rate (BMR) when estimated from carbon dioxide production. It is calculated from the ratio of carbon dioxide produced by the body to oxygen consumed by the body

48

When can the RQ go above 1?

During fasting

After heavy physical work

During conversion of amino acids to carbohydrates

During conversion of carbohydrates to fat

During conversion of carbohydrates to fat

49

When can the RQ go below 0.7?

During conversion of amino acids to carbohydrates

During conversion of carbohydrates to fat

During hyperventilation

During metabolic acidosis

During conversion of amino acids to carbohydrates

50

What is the normal setup for Atwater- Rosa type calorimetry?

The animal is placed into a chamber which is surrounded with ice - heat production is calculated by the amount ice melted

In the closed system the animal inspires a known amount of oxygen, the measurement of CO2 can be omitted

It is a combination of direct and indirect calorimetry

It works like an open-system indirect calorimetry, furthermore the heat production of the animal can be measured directly

It is a combination of direct and indirect calorimetry

51

What does the Kleiber's equation describe?

Basal metabolic rate shows a linear correlation with the body mass

The relative metabolic rate is higher in a large animals than in small ones

The metabolic rate as a logarithmic function of the body mass appears as a line with a slope of 0.5

metabolic rate is a function of the 0.75th power of body weight

metabolic rate is a function of the 0.75th power of body weight

52

What is the correlation between the metabolism and the body surface?

logarithmic
linear
exponential
no correlation

Logarithmic

53

Which of the below hormones has no effect on the metabolic rate?

Thyroid hormones
Calcitonin
Male sexual steroids
Growth hormone

Calcitonin

54

When does the metabolic rate decrease?

During increased production of thyroid hormones

During sympathetic activation

During sleeping

During growth hormone production

During sleeping

55

What is the specific dynamic action?

The proportion of energy which can be converted to metabolic energy

The proportion of energy which can be stored in the body

The energy released during the oxidation of foodstuff

The energy required for assimilation of foodstuff.

The energy required for assimilation of foodstuff.

56

Which of the below nutrients has the highest specific dynamic action?

Protein
fat
carbohydrates
volatile fatty acids

Protein

57

Which is the most important component of the specific dynamic action?

Energy used for digestion

Energy used for deamination in the liver

Energy used for absorption

Energy used for storing processes

Energy used for deamination in the liver

58

How will the metabolic rate change after food intake?

Decreases for 1-2 hours

Increases after an hour and remains high for 2-3 more hours

Increases after an hour then decreases

Does not change

Increases after an hour and remains high for 2-3 more hours

59

How does the body temperature alter the metabolic rate?

It does not change the metabolic rate

Decreasing body temperature increases metabolic rate

Increasing body temperature decreases metabolic rate

Increasing body temperature increases metabolic rate

Increasing body temperature increases metabolic rate

60

How does the environmental temperature alter the metabolic rate?

Metabolic rate is increased both below lower and above upper critical temperatures

Metabolic rate is decreased below the lower critical temperature and increases above the upper critical temperature

Metabolic rate is increased below the lower critical temperature and decreases above the upper critical temperature

The environmental temperature does not alter the metabolic rate significantly

Metabolic rate is increased both below lower and above upper critical temperatures

61

What is true for the body temperature of poikilothermic mammals?

the surface temperature of the body may change as a function of the environmental temperature

the core temperature of the animal changes according to the change in the surface temperature

the body temperature is constant all through the animal's life

in some periods of the day, the fodder ingestion and muscle activity have an effect on the body temperature

the surface temperature of the body may change as a function of the environmental temperature
(bat, hummingbird)

62

What is true for the body temperature of heterothermic animals?

the body temperature changes as a function of environmental temperature

the core temperature is independent of the environmental temperature but in certain physiological periods it may change

the body temperature is unrelated to environmental temperature

in some periods of the day, the fodder ingestion and muscle activity have an effect on the body temperature

The core temperature is independent of the environmental temperature but in certain physiological periods it may change

63

What is true for the body temperature of homeothermic animals?

the body temperature changes as a function of environmental temperature

the body temperature is unrelated to environmental temperature, in certain physiological periods the animal's temperature depends on the environmental temperature

the body temperature is unrelated to environmental temperature throughout the animal's life

the fodder ingestion and muscle activity have an effect on the core temperature

the body temperature is unrelated to environmental temperature throughout the animal's life

64

What has no effect on the core temperature?

muscle activity
feed ingestion
age
environmental temperature

Environmental temperature

65

What is true for the peripheral temperature of animals?

the temperature of the tissues which are in direct contact with the environment changes

the peripheral temperature and the core temperature change parallelly

the temperature of the tissues which are in direct contact with the environment is constant

the peripheral temperature is changed only by an extremely large change in the environmental temperature

the temperature of the tissues which are in direct contact with the environment changes

66

Which statement is correct for the core temperature of hibernating animals?

the core temperature is the same as the environmental temperature

the animals wake up regularly when their core temperature rises

the temperature in the intestine does not cool down in these animals

during the hibernation the core temperature is a little bit lower than the environmental temperature

The animals wake up regularly when their core temperature rises

67

What is aestivation?

a special form of hibernation in cold

the accumulation of fat for hibernation

it is a dormant state in summer

during a very cold night the animal becomes active

It is a dormant state in summer

68

What is the torpor?

it is the inactive state of the metabolism when the weather is hot and dry

the animals temperature increases continuously

it is active muscle work occurring to survive the cold period

during the cold night the animal becomes numb and its body temperature approaches the environmental temperature

during the cold night the animal becomes numb and its body temperature approaches the environmental temperatur

69

Which factor influences the normal core temperature the most?

Time of day
Age
Fodder ingestion
Sex

Age

70

How does the thermoneutral zone change with age?

the older the animal is, the narrower is the thermoneutral zone

the thermoneutral zone is not present in young animals

the younger the animal is, the narrower is the thermoneutral zone

age is unrelated to the neutral zone

the younger the animal is, the narrower is the thermoneutral zone
?

71

Why do the young animals have higher body temperatures?

the body surface is relatively small

they have worse adaptability to the environmental temperature than the older ones

they have a better adaptability to the environmental temperature than the older ones

they have a larger metabolic rate than the older ones

they have a larger metabolic rate than the older ones

72

Which factor does not belong to the exchangeable quantity of heat?

metabolic heat
conductive heat
radiation heat
evaporative heat

Metabolic heat

73

What best describes the radiation heat loss?

it is mediated by air

it is linearly related to the body surface area

it is exponentially related to body surface area

it is linearly related to the distance between the animal and the surrounding objects

it is exponentially related to body surface area

74

Which substance is the best heat conductor?

Epidermis
Hair
Muscle
Air

Muscle

75

Which process generates heat?

Radiation
Conduction
Piloerection
Shivering

Shivering

76

Which process results in no heat loss?

Piloerection
Evaporation
Conduction
Radiation

Piloerection

77

What is true for the thermoneutral zone?

This zone is constant in all species

In this zone the metabolic rate does not change

The body temperature is the lowest in this zone.

It is a part of the optimal zone

In this zone the metabolic rate does not change

78

What is characteristic of the optimum zone?

It is lower point is the Lower Critical Temperature

there is no metabolism in this phase

it is within the thermoneutral zone, the animal prefers this temperature

its upper point is the Upper Critical Temperature

it is within the thermoneutral zone, the animal prefers this temperature

79

What can changes below the Lower Critical Temperature be observed?

When energy production decreases but the body temperature does not change

when energy production and body temperature both decrease

when energy production increases and body temperature gradually decreases

energy production increases but the body temperature basically does not change

energy production increases but the body temperature basically does not change

80

What can changes above the Upper Critical Temperature be observed?

When energy production increases, first the temperature does not change but then increases

When energy production increases and the body temperature decreases or does not change

When energy production decreases and body temperature increases

When energy production decreases but body temperature does not change

When energy production increases, first the temperature does not change but then increases

81

What changes can be observed in hypothermia?

energy production increases and body temperature decreases

both energy production and body temperature decrease

energy production increases but body temperature does not change

energy production decreases but body temperature does not change

both energy production and body temperature decrease

82

What changes can be observed in hyperthermia?

energy production decreases but body temperature does not change

energy production does not change but body temperature increases

energy production decreases and body temperature increases

neither energy production nor body temperature changes

energy production decreases and body temperature increases

83

Which temperature interval listed below is the widest?

the one between the lower and the upper critical temperature

the optimum zone

the thermoneutral zone

the interval that can still be regulated

the interval that can still be regulated

84

Which are the physical elements of protection against the cold?

cuddling, shivering, chemical thermogenesis

perspiratio sensibilis and insensibilis

radiation, convection, conduction

spontaneous, synchronized contractions of the muscles, increase of metabolism

cuddling, shivering, chemical thermogenesis

85

What is the shivering thermogenesis?

defence mechanism - behavioral changes

thermogenic mechanism - the increase of muscular activity

heat produced during the enzymatic break- down and oxidation of body fat

utilization of thermal energy obtained from the outsid

thermogenic mechanism - the increase of muscular activity

86

What is conductive heat loss?

heat loss through water or air coming into contact with the body

heat loss in the form of electromagnetic waves

heat loss by coming in direct contact with a cold object

heat loss through water vaporization

heat loss by coming in direct contact with a cold object

87

What is convective heat loss?

heat loss by coming into direct contact with a cold object

heat loss in the form of electromagnetic waves

heat loss through liquid evaporized from the body surface

heat loss through water or air coming into direct contact with the body

heat loss through water or air coming into direct contact with the body

88

What is characteristic of radiation heat loss?

heat loss in the form of electromagnetic waves

heat loss by coming into direct contact with a cold object

heat loss through water or air coming into direct contact with the body

heat loss through water evaporation

heat loss in the form of electromagnetic waves

89

Which one is a "wet" form of heat loss?

conduction
evaporation
convection
radiation

Evaporation

90

Behavioral response is a part of which protective mechanism?

protection from cold

protection from heat

part of protection from both cold and heat

not part of the protection either from heat nor from cold

part of protection from both cold and heat

91

What are the advantages of panting?

during panting protection from heat needs no work investment

water loss is prevented by panting

all animal species are capable of heat loss through panting

the animal can regulate the extent of the heat loss through panting

the animal can regulate the extent of the heat loss through panting

92

To which heat loss mechanism does panting belong to?

perspiratio insensibilis
perspiratio sensibilis
conduction
radiation

perspiratio insensibilis

93

How much heat is needed to vaporize of 1 g of water?

2.4 kcal
0.58 kcal
0.58 kJ
5.8 kJ

0.58 kcal

94

Which animals contain sweat glands on their skin?

guinea-pig
rabbit
cattle
birds

Cattle

Horse?

95

Which animal does not have sweat glands?

rat
dog
cattle
rabbit

Rabbit

96

Sweating belongs to what heat loss mechanism?

perspiratio sensibilis
perspiratio insensibilis
conduction
convection

perspiratio sensibilis

97

What changes in the blood circulation can be observed in a hot environment?

the arteriovenosus anastomoses open up, the precapillary sphincters in the skin are closed, blood is led through the deep veins

the arteriovenosus anastomoses open and allow intensive perfusion in the surface regions

the precapillary sphincters are closed, venous blood is conducted through the surface veins

the precapillary sphincters are open, venous blood is conducted through the deep veins

the arteriovenosus anastomoses open and allow intensive perfusion in the surface regions

98

What characteristics of the blood circulation can be observed in cold environment?

the precapillary sphincters are closed, venous blood is conducted through the surface veins

the arteriovenosus anastomoses close and the precapillary sphincters close too so that blood is directed back to deep veins

the arteriovenous anastomoses are closed and the blood is led into capillaries of the skin, then it is conducted though the surface veins

the precapillary sphincters are open and venous blood is conducted through the deep veins

the arteriovenosus anastomoses close and the precapillary sphincters close too so that blood is directed back to deep veins

99

Which special structure ensures the protection of the testes in heat?

the looping exchanger system
rete mirabile
carotis rete
plexus pampiniformis

plexus pampiniformis

100

Which special structure ensures the protection of the feet of wading birds in the cold?

rete mirable
carotis rete
plexus pampiniformis
looping heat exchanger

Rete mirable

101

Which anatomical structure is protected from heat by the carotis rete?

the mucous membrane of the nose
brain and central nervous system
heart
sense organs

brain and central nervous system

102

What constitutes the afferentation of thermoregulation?

the set-point of the thermostate

stimulus starting from a receptor-site in the spinal cord

stimulus starting from the peripheral and central thermoreceptors informing the thermostate of the hypothalamus

stimulus originating from the peripheral cold receptors

stimulus starting from the peripheral and central thermoreceptors informing the thermostate of the hypothalamus

103

Where is the temperature control center?

in the pons
in the medulla oblongata
in the thalamus
in the hypothalamus

in the hypothalamus

104

What determines the value of the intrinsic core temperature?

the "set point" of temperature center of the hypothalamus

the "current" value of peripherial receptor system

the "must" value of the hypothalamic receptors

the "current" value of temperature center of the hypothalamus

the "set point" of temperature center of the hypothalamus

105

What are the practical occurrences of hypothermia?

fresh sheared sheep in rainy weather

in old, weaker animals in prolonged cold

heat loss in new born animals

in young animals in rainy, cold weather

heat loss in new born animals

106

What is true for hyperthermia?

the animals endure hyperthermia easier, than hypothermia

hypercapnia, paralysis of muscle

metabolism increases important, increasing of heart frequency cause the collapse of circulation

it results in insufficient function of temperature regulation

it results in insufficient function of temperature regulation

107

What kind of animal is the most sensitive to hypothermia?

piglets
horses
calves
chickens

Piglets

108

What is true for fever?

it affects adversely the organism

regulated hyperthermia which is caused by inflammation, destruction of tissue or any other disease

it is a special form of hyperthermia when temperature control falls out

it is caused by peripheral heat sensors

Regulated hyperthermia which is caused by inflammation, destruction of tissue or any other disease

109

What is an exogenous pyrogenic substance?

I1-and IL-6compounds which are produced during activation of macrophage

prostaglandin

endotoxin of Gram negative bacteria

it is a special protein which is produced in heat center of hypothalamus

endotoxin of Gram negative bacteria

110

Pyrogenic

Fever inducing

111

What happens at the beginning of a fever?

above all the organism increases the body temperature by heat conservation

the heat pass courses are activated

the "current" value is larger than the "must" value

the fever causes the increase of the "must" set point in the hypothalamus

the fever causes the increase of the "must" set point in the hypothalamus

112

What occurs at the end of a fever?

the "must" value returns back to the normal level and cooling mechanisms start

the "must" value of hypothalamus increases

heating mechanisms are activated

shivering is experienced

the "must" value returns back to the normal level and cooling mechanisms start

113

What kind of morpho-functional changes occur during cold acclimation?

secretion of glucocorticoids

the fur/feathers become stronger, the heat insulation thickens

vasodilatator mechanism activates

brown adipose tissue atrophies

the fur/feathers become stronger, the heat insulation thickens

114

Which is not true for heat acclimation?

thickness of the heat insulators decrease

vasodilator mechanism activates

function of breathing muscles decreases

sweat gland activates

function of breathing muscles decreases

115

Which substance ensures uncoupling during cellular thermogenesis?

special 23000kDa mass glucoproteid
cAMP
FFA
thermogenin

thermogenin (UCP 1)

116

Which hormones influence uncoupling?

thyroxine, epinephrine

glucocorticoid, epinephrine

norepinephrine, STH

FSH, STH

thyroxine, epinephrine

117

What is the function of thermogenin during the uncoupling mechanism?

it increases the catabolism of FFA

it allows protons to flow through the mitochondrial membranes without producing ATP

it inhibits the catabolism of ATP

it directly increases glucose uptake by the cells

it allows protons to flow through the mitochondrial membranes without producing ATP

118

In which tissue does uncoupling occur in?

white adipose tissue
liver
brown adipose tissue
muscle

Brown adipose tissue