Temperature Regulation MCQs

What is the receptor for adrenaline in the brown adipose tissue that can cause chemical thermogenesis?

a) α1-adrenoreceptors

b) α2-adrenoreceptors

c) β2-adrenoreceptors

d) β1-adrenoreceptors

e) β3-adrenoreceptors

e) β3-adrenoreceptors

When measured orally the average normaltemperature 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) 36.6-37.0°C

Which hormone is not related to thermogenesis:

a) vasopressin

b) adrenaline

c) noradrenaline

d) thyroxine

e) cortisol

a) vasopressin

Thermoreceptors are:

a) only found in the skin

b) peripheral and central

c) a subtype of electromagnetic receptors

d) on the dendritic endings of B fibres

e) only for hot

b) peripheral and central

According to the circadian rhythm the body temperature is:

a) the lowest in the afternoon and the highest in the morning

b) the lowest at midnight and the highest at noon

c) the highest at midnight and the lowest at noon

d) the highest in the morning and the lowest at noon

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

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

A major means for conserving heat is:

a) vasodilatation of cutaneous blood vessels

b) increased metabolic rate

c) vasoconstriction of cutaneous blood vessels

d) enhanced sweating

e) increased convective loss

c) vasoconstriction of cutaneous blood vessels

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

Which one of the following is produced by sebaceous glands?

a) adrenaline

b) oil

c) saliva

d) sweat

e) mucus

b) oil

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) the ability to lose heat by sweating

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) by evaparation; depend on the activity of sweat glands being under sympathetic muscarinic control

At which temperature does the excitation of the thermoreceptors begin to cause pain?

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) over 45°C

Where are the brown thermogenic adipocytes located in the adult?

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

The most significant heat source in the body is:

a) cellular respiration

b) conductive heat loss

c) convective heat loss

d) evaporation

e) sweating

a) cellular respiration

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) 37°C

The thermoregulatory center is located in:

a) cortex

b) vascular system

c) septal region

d) amygdale

e) hypothalamus

e) hypothalamus

When the temperature of environment is above 34°C, the only heat-loss mechanism is:

a) convection

b) radiation

c) shivering

d) evaporation

e) radiation and convection

d) evaporation

The set point level for body temperature is situated in:

a) anterior hypothalamus

b) skin

c) spinal cord

d) posterior hypothalamus

e) brown mast tissue

d) posterior hypothalamus

The highest body temperature is in:

a) the kidneys

b) the liver

c) the intestines

d) the spleen

e) the lungs

b) the liver

The most potent 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) shivering

Which of the following is a human thermoregulatory response controlled by cholinergic sympathetic nerves?

a) brown adipose tissue thermogenesis

b) hand vasomotion

c) shivering thermogenesis

d) sweat secretion

e) thermoregulatory behavior

d) sweat secretion

The most important function of sweat is to remove from the body excess:

a) heat

b) salts

c) water

d) urea

e) bilirubin

a) heat

Which response to overcooling does not involve muscle contraction?

a) blood vessels narrowing

b) hairs standing up

c) shivering

d) reduced sweating

e) hyperventilation

d) reduced sweating

The heat balance is negative when:

a) heat production is bigger than heat loss

b) heat production equals heat loss

c) heat production is less than heat loss

d) there is no heat loss

e) there is heat loss, independently of heat production

c) heat production is less than heat loss

When does a woman's rectal temperature rise?

a) in lactation

b) in menopause

c) in menstruation

d) in ovulation

e) in fertilization

d) in ovulation

What process is not related to heat balance:

a) conduction

b) evaporation

c) convection

d) accommodation

e) radiation

d) accommodation

What happens to 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 the surrounding tissues

e) they constrict

b) they dilate and become wider

What weather conditions make it harder to evaporate sweat?

a) hot and dry weather

b) cold and humid weather

c) cold and dry weather

d) hot and humid weather

e) sweat evaporation is independent of the weather

d) hot and humid weather

The main mechanism for heat exchange of the body immerced in water is:

a) evaporation

b) convection

c) friction

d) conduction

e) the listed mechanisms have equal importance

d) conduction

Physiological thermoregulatory mechanisms include:

a) chemical thermogenesis

b) sweating

c) non-chemical thermogenesis

d) vasomotor reactions

e) all of the above

e) all of the above

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) imperceptible evaporation through the skin and lungs

Cutaneous thermoreceptors for cold are terminal branches of:

a) Aγ -fibers

b) Aβ-fibers

c) Aδ-fibers and C-fibers

d) B-fibers

e) motor fibers

c) Aδ-fibers and C-fibers

Cutaneous thermoreceptors for warmthare terminal branches of:

a) Aγ -fibers

b) Aβ-fibers

c) Aδ-fibers

d) B-fibers

e) C-fibers

e) C-fibers

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) 6° C

Which of the listed hormones is not related to thermogenesis:

a) vasopressin

b) adrenaline

c) norepinephrine

d) thyroxine

e) cortisol

a) vasopressin

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) evaporation

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) the paradoxical (REM) sleep

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 by cholinergic sympathetic innervation

e) does not exist

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