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.
Melanocyte, specialized skin cell that produces the protective skin-darkening pigment melanin. Birds and mammals possess these pigment cells, which are found mainly in the epidermis, though they occur elsewhereâe.g., in the matrix of the hair. Melanocytes are branched, or dendritic, and their dendrites are used to transfer pigment granules to adjacent epidermal cells.