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.
Epidermis: The upper or outer layer of the two main layers of cells that make up the skin. The epidermis is mostly made up of flat, scale-like cells called squamous cells. Under the squamous cells are round cells called basal cells. The deepest part of the epidermis also contains melanocytes. These cells produce melanin, which gives the skin its color. The other main layer of the skin is the dermis, the inner layer of skin, that contains blood and lymph vessels, hair follicles, and glands. These glands produce sweat, which helps regulate body temperature, and sebum, an oily substance that helps keep the skin from drying out.