AP BIOLOGY

LABORATORY REVIEW

MOLECULAR BIOLOGY

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
Why do we sweat? When water evaporates, it ____ a lot of energy from the system due to the fact that it has a high latent heat of evaporation. This is felt as a ____ sensation.
A
removes, cooling
B
removes, heating
C
adds, cooling
D
adds, heating
Explanation: 

Detailed explanation-1: -That’s because cooling your body via sweating relies on a principle of physics called “heat of vaporization.” It takes energy to evaporate sweat off of your skin, and that energy is heat. As your excess body heat is used to convert beads of sweat into vapor, you start to cool down.

Detailed explanation-2: -When the sweat hits the air, the air makes it evaporate (this means it turns from a liquid to a vapor). As the sweat evaporates off your skin, you cool down. Sweat is a great cooling system, but if you’re sweating a lot on a hot day or after playing hard you could be losing too much water through your skin.

Detailed explanation-3: -The heat that is absorbed when perspiration evaporates (by breaking bonds between water molecules, thereby increasing its potential energy) is called the latent heat of vaporization.

Detailed explanation-4: -In humid conditions where surrounding air cannot hold further water vapour, sweat evaporates slowly, if at all. As a result the body heats up. it is difficult for the sweat to evaporate and in high humidity conditions we tend to sweat more. This explains why it feels so much hotter in high humidity.

There is 1 question to complete.