Call your doctor if your baby: 1  Is under 3 months old and has a temperature over 100.4 F. 2  Is over 3 months old and has a fever over 102 F. 3  Has a fever that lasts longer than 24 hours.  Has diarrhea, vomiting, or a rash with the 1  fever. Is very sleepy or looks sick.  Can't be soothed.
There is two main pigments found in human hair: Eumelanin has an oval or elliptical shape, which gives color to brown or black hair and is dark pigment. The higher the concentration of Eumelanin the darker the hair. Pheomelanin is what produces the color in blonde or red hair.
The change in hair color occurs when melanin ceases to be produced in the hair root and new hairs grow in without pigment. The stem cells at the base of hair follicles produce melanocytes, the cells that produce and store pigment in hair and skin.