X. TEMPERATURE REGULATION

1. What is the receptor for adrenaline in the brown adipose tissuethat

can cause chemical thermogenesis?

a) a1-adrenoreceptors;

b) d2-adrenoreceptors;

c) B2-adrenoreceptors;

d) B1-adrenoreceptors;

e) p3-adrenoreceptors.

e

2. When measured orally the averagenormal temperature is considered to

be:

a) 36.0-36.6°C;

b) 36.5-37.5°C;

c) 36.6-37.0°C;

d) 37.0-37.5°C;

e) 35.5-36.5°C.

c

3. Which hormone is not related to thermogenesis:

a) vasopressin;

b) adrenaline;

c) noradrenaline;

d) thyroxine;

e) cortisol.

a

4. Thermoreceptors are:

a) only found in the skin;

b) peripheral and central;

c) a subtypeof electromagnetic receptors;

d) on the dendritic endings of B fibres;

e) only for hot.

b

5. According to the circadian rhythm the body temperatureis:

a) the lowest in the afternoon andthe highest in the morning; b) the lowest at midnight and the highest at noon;

c) the highest at midnight andthe lowest at noon;

d) the highestin the morning and the lowestat noon;

e) the highest in the afternoon and the lowest in themorning

e

6. A major meansfor conserving heat is:

a) vasodilatation of cutaneous blood vessels;

b) increased metabolic rate;

c) vasoconstriction of cutaneous blood vessels;

d)enhanced sweating;

increased convectiveloss.

c

7. Heatstroke is characteristically associated with:

a) profuse sweating;

b) elevated basal metabolic rate (BMR) and hot dry skin;

c) cold dry skin;

d) decresed basal metabolic rate(BMR);

e) decreased heart rate (HR).

b

8. Which one of the following is produced by sebaceous glands?

a) adrenaline;

b) oil;

c)saliva;

d)sweat;

e)mucus.

b

9. Following adaptation to a hot climate there is an increase in:

a) basal metabolic rate;

b) heat loss by radiation and convection;

c) urinary output;

d) the ability to lose heat by sweating;

e) decreasing arteriovenous shunting of blood to venous plexus near

the surface of the skin.

d

10. Heat-loss mechanisms:

a) cause shivering;

b) by evaparation; depend on the activity of sweat glands being

under sympathetic muscarinic control;

c) are controlled by the anterior hypothalamus;

d) cause an increase in sympathethic tone to skin blood vessels;

e) decrease arteriovenous shunting of blood to venous plexus near the

surface of the skin.

b

11. Atwhich temperature does the excitation of thethermoreceptors begin

to causepain?

a) at the temperature which causes tissue damage;

b) over 45°C

c) at 30°C;

d) at 5°C;

e) at 35°C.

b

Where are the brown thermogenic adipocytes located in the adult?

12.

a) in the pulp of the spleen;

b) between the scapulas, around the kidneys and the big vessels.

c) in the bone marrow;

d) in the capsule of the liver;

e) in the parietal and visceral layers of the pleura and the pericardium;

b

13. The most significant heat source in the bodyis:

a) cellular respiration;

b) conductive heat loss;

c) convective heat loss;

d) evaporation;

e) sweating

a

14. The set-point temperature of the hypothalamus, triggering heat loss or

heat-generating mechanisms is:

a) 34°C;

b) 37°C;

c) 20°C;

d) 36.6°C;

e) 38°C.

b

15. The thermoregulatory center is located in:

a) cortex;

b) vascular system;

c) septal region;

d) amygdale;

e) hypothalamus.

e

16. When the temperature of environtment is

mechanism is:

above 34°C, the onlyheat-loss

a) convection;

b) radiation;

c) shivering;

d) evaporation;

e) radiation and convection.

d

17. The set point level for bodytemperature is situated in:

a) anterior hypothalamus;

b) skin;

c) spinal cord;

d) posterior hypothalamus;

e) brown mast tissue.

d

18. The highest body temperature is in:

a) the kidneys;

b) the liver;

c) the intestines;

d) the spleen;

e) the lungs.

b

19. The mostpotent mechanism for increasing heat production is:

a) activation of the parasympathetic nervous system;

b) thyroid hormone increasing the metabolic rate;

c) shivering;

d) radiation;

e) decrease in sympatetic tone to skin blood vessels.

c

20. Which of the following is a human thermoregulatory response

controlledbycholinergic sympathetic nerves?

a) brown adipose tissue thermogenesis;

b) hand vasomotion;

c) shivering thermogenesis;

d) sweat secretion;

e) thermoregulatory behavior.

d

21. The most important function of sweat is to remove from the body

excess:

a) heat;

b) salts;

C) water

d) urea

e) bilirubin

a

22.Which

response to overcooling does not involvemuscle contraction?

a) blood vesselsnarrowing;

b) hairs standingup;

c)shivering;

d) reduced sweating;

e) hyperventilation

d

23. The heat balance is negative when:

a) heat production is bigger than heat loss;

b) heat production equals heatloss;

c) heat production is less than heat loss;

d) there is no heat loss;

e) there is heat loss, independently of heat production

c

23. The heat balance is negative when:

a) heat production is bigger than heat loss;

b) heat production equals heatloss;

c) heat production is less than heat loss;

d) there is no heat loss;

e) there is heat loss, independently of heat production

d

25. What process is not related to heat balance:

a) conduction;

b)evaporation;

c) convection;

d)accommodation;

e) radiation.

d

26. Whathappensto the arterioles near the surface of the skin when the

body temperature rises?

a) they absorb oxygen from the surrounding tissues;

b) they dilate and become wider;

c) they move nearer the skin surface;

d) they take in water from thesurrounding tissues;

e) they constrict.

b

27. What weather conditions make it harder

a) hot and dry weather;

to evaporate sweat?

b) cold and humid weather;

c) cold and dry weather;

d)hot and humid weather;

e) sweat evaporation is independent of the weather

d

28. Themain mechanism for heat exchange of the bodyimmerced in water

is:

a) evaporation;

b) convection;

c) friction;

d) conduction;

e) the listed mechanisms have equal importance.

d

29. Physiological thermoregulatory mechanisms include:

a) chemical thermogenesis;

b) sweating;

c) non-chemical thermogenesis;

d) vasomotor reactions;

e) all of the above.

e

30. Perspiratio insensibilis is:

a) profuse sweating;

b) excretion of water from the digestive system;

c) emotional sweating;

d) lack of sweating;

e) imperceptible evaporation through the skin and lungs.

e

31. Cutaneous thermoreceptors for cold are terminal branches of:

a) A1 -fibers;

b) AB-fibers;

c) A8-fibers and C-fibers;

d) B-fibers;

e) motor fibers.

c

32. Cutaneous thermoreceptors forwarmthare terminal branches of:

a) Ax -fibers;

b) AB-fibers;

c) A8-fibers;

d) B-fibers;

e) C-fibers.

e

33. The usual temperature gradient between the core and

body surface area is about:

a) 10° C;

b) 6° C;

c) 3° C;

d) 1° C;

e) 0.5° C.

b

34. Which of the listed hormones is not related to thermogenesis:

a) vasopressin;

b) adrenaline;

c) norepinephrine;

d) thyroxine;

e) cortisol.

a

35. At an ambient temperature above 31°C, the main release mechanism

of heat is:

a) convection;

b) radiation;

c) conducting;

d) evaporation;

e) shivering.

d

36. Thermoregulatory mechanisms are ineffective during:

a) the paradoxical (REM) sleep;

b) first phase of slow-wave sleep;

c) second phase of slow-wave sleep;

d) third phase of slow-wave sleep;

e) fourth phase of slow-wave sleep.

a

37. Which statement about emotionally induced sweating is true:

a) it is diffuse;

b) goes away relatively slowly;

c) it is adrenergic and depends on the circulating level of adrenaline;

d) is affected bycholinergic sympathetic innervation;

e) does not exist.

c