Plotting the Distribution of Sweat Glands. With what substance does the bond paper react when iodine is painted on the skin? Based on class data, which skin area has more sweat glands, the forearm or the palm of the hand? Was this an expected result? Explain. Which other body areas would be tested for high density sweat glands? What organ system controls the activity of the eccrine sweat glands? Dermography: Fingerprinting. Why can fingerprints be used to identify individuals? Name the three main fingerprint patterns. Arckes, JedS, Adc, Kenna, and tamoc are temporary tattoos that last about 12 days. Hypothesize why henna tattoos do not last as long as permanent tattoos. Vitiligo. Why is the pigmentation of the skin uneven, resulting in white patches? Vitiligo might be a recent autoimmune disorder. Which cells would you expect to be most affected, and why?