Trypanosomiasis refers to a group of diseases caused by Trypanosoma There are two types of trypanosomiasis that affect humans, they are divided according to their geographical location: African trypanosomiasis, or sleeping sickness, is caused by Trypanosoma brucei parasites in sub-Saharan Africa and is transmitted by the tsetse fly? (Glossina).
Specilized cells in the epidermis called melanocytes produce melanin, a dark pigment that provides skin color. Melanin absorbs ultraviolet radiation in sunlight and preventing mutations in the DNA of skin cells and other damaging effects.ifferences in skin color result from differences in the amount of melanin that melanocytes produce and the distribution and size of pigment granules. Skin color is genetically determined.
abstract melanocytes are an essential cell type found in the skin and hair these cells provide pigmentation and thus photoprotection from ultraviolet radiation current understanding of the process of pigmentation comes from studying pigmentation mutants in a variety of speciesn embryonic day 14 5 melanocytes exit from the overlying dermis and populate the epidermis and developing hair follicles melanocytes also travel to the leptomeninges iris choroid of the posterior eye and stria vascularis of the cochlea