Question 26 Which of the following statements about body temperature homeostasis

Question

Question 26

Which of the following statements about body temperature homeostasis is correct?

Body temperature is a balance between heat loss and heat gain.

Core temperature is maintained at 34°C.

Skin temperature is always equal to core temperature.

All of the above statements are correct.

Which of the following is not a reason stroke volume increases with acute exercise or exercise training?

A.

Increase preload (EDV)

B.

Increase plasma volume

C.

Increase venous return

D.

Increase muscle blood flow

E.

Increase afterload or peripheral resistance

Question 26

Which of the following statements about body temperature homeostasis is correct?

Body temperature is a balance between heat loss and heat gain.

Core temperature is maintained at 34°C.

Skin temperature is always equal to core temperature.

All of the above statements are correct.

Which of the following is not a reason stroke volume increases with acute exercise or exercise training?

A.

Increase preload (EDV)

B.

Increase plasma volume

C.

Increase venous return

D.

Increase muscle blood flow

E.

Increase afterload or peripheral resistance

Body temperature is a balance between heat loss and heat gain.

Core temperature is maintained at 34°C.

Skin temperature is always equal to core temperature.

All of the above statements are correct.

Explanation / Answer

Which of the following statements about body temperature homeostasis is correct?

Ans. Body temperature is a balance between heat loss and heat gain(Only OPTION 1 is correct)

Because body temperature homeostasis is based on regulatory mechanisms to maintain the body temperature in the range of 36.5-37.50C or 97.7-99.50F. If the temperature rises blood vessels constrict, sweat glands do not perspire and there is involuntary contraction of muscles(shivering) which helps in generation of heat(HEAT GAIN)

On the otherhand, If there is rise in body temperature, blood vessels are dilated, perspiration occurs and when sweat is evaporated, heat is lost from the body(HEAT LOSS) which brings the normal body temperature

So body temperature homeostasis can be described as a balance between heat loss and heat gain. The given option is correct.

The second option which states that Core temperature is maintained at 34°C is FALSE. But as mentioned earlier, the normal body temperature is in the range of 36.5-37.50C or 97.7-99.50F which is very essential to maintain essential body functions. If the body temperature is less than 350C it is regarded as Hypothermia which is dangerous

The 3rd option, Skin temperature is always equal to core temperature is also NOT CORRECT. Because the core temperature is always higher than peripheral (skin) temperature which is found to be differed by 0.270C or 0.50F(Core temperature is more by 0.270C or 0.50F than peripheral temperature)

Since 2, 3 are wrong option 4 is also wrong. Hence option is correct.

Which of the following is not a reason stroke volume increases with acute exercise or exercise training?

Answer: Option E: Increase afterload or peripheral resistance. Because if afterload or peripheral vascular resistance is increased it reduces stroke volume. Hence it is NOT a reason for increase in Stroke volume. During exercise, afterload is reduced

Explanation:

Option A: EDV is the volume of blood in the ventricles before systole, during exercise, the venous return is increased which ultimately increases the preload or EDV. Hence, it is true.

Option B. Increase in plasma volume. Because due to increased perspiration and lower haematocrit values, there will be an adaptation for increased plasma volume in athletes as seen in endurance training. which is responsible for increase in stroke volume.

Option C. During exercise venous return(amount of blood that is reaching the heart) is increased due to increased work and mobilisation of blood from muscles to the heart that leads to complete filling followed by complete emptying (as explained by Frank starling mechanism) that tends to increase both stroke volume as well as cardiac output

Option D: Increased muscle blood flow. Because, hypoxia in the muscles leads to increase muscle blood flow that leads to increase in stroke volume.

Related Questions

Navigate

• Browse (All)
• Browse Q
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.