Can Sweat Composition Change

Not only can sweat vary in how much is produced but it can also vary in composition. By and large the final concentration of sweat depends on how rapidly it is produced. As shown in Figure 7.2, our sweat glands are based pretty deep in our skin. When we sweat, the initial fluid oozing into the tubes leading to our skin surface is concentrated with sodium and chloride and similar to the concentration in our blood (plasma). As that sweat flows through the tube, sodium and chloride can be absorbed back into our body along with some of the water. What is most important in determining the final amount and composition of the sweat reaching our skin surface is how rapid the sweat flows through the tubes, which itself is related to the strength of stimulation. When the flow of sweat through the tubes is faster, more sweat reaches the skin and less and less sodium, chloride, and other factors are reabsorbed. As the sweat evaporates it leaves the once-dissolved substances on our skin, which can cake on a drier day.

0 0

Post a comment