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.
This thin, most superficial layer of the skin forms the interface with the external environment and has special protective functions. 1  Melanocytes. 2  These cells produce a dark pigment called melanin which contributes to skin color and provides UV protection.elanocytes and Langerhans cells are other important cells found in the epidermis which have special functions. Dermis. The dermis consists mostly of connective tissue and is much thicker than the epidermis.