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.
As the hair is being formed, melanocytes inject pigment (melanin) into cells containing keratin. Keratin is the protein that makes up our hair, skin, and nails. Throughout the years, melanocyctes continue to inject pigment into the hairâs keratin, giving it a colorful hue. With age comes a reduction of melanin.arents often cite having teenagers as the cause of gray hair. This is a good hypothesis, but scientists continue to investigate why hair turns gray. In time, everyoneâs hair turns gray. Your chance of going gray increases 10-20% every decade after 30 years.