Question

ths question is from essential of human anatomy and physiology 11 edition. chapter 2

. Sarah is quite proud of her slender, model like figure and boasts that she doesn’t have an “ounce of excess body fat”. Lauren, in contrast, on the other hand, is grossly overweight. She complains of feeling hot most of the time, and on a hot day she is miserable. Sarah generally feels chilled except on very hot days. Explain the relative sensitivity to environmental temperature of these two women on the basis of information you have been given in the organic compounds section of this chapter.

Answer 1

Lauren who is overweight has more subcutaneous fat compared to Sarah. Subcutaneous fat play a major role in heat production . Heat is trapped inside the body to maintain constant internal bodytemperature for physiological process to occur. This body temperature increases through physical activities like active work, excercise etc. The person who is obese has extra layer of fat and heat gets trapped inside the body due to small surface area.But person who is thin has large surface area and subcutaneous fat is also less hence heat dissipates fast and they feel less hot compared to overweight persons. The same explanation holds good for hands and fingers ie the surface area is large for fingers and heat gets dissipated fast and that is why hands gets colder fast in winters compared to body.

Hence Sarah feels colder to Lauren in hot days.