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.
In the deepest layer of the epidermis, the stratum basale, which is also sometimes called the basal layer, are cells called melanocytes. These are cells that produce the pigment melanin. It is this substance, melanin, which determines the skin color of an individual.he Dermis. Furthermore, in serious cases of sunburn, even the next layer of skin, the layer right underneath the epidermis, can be affected. This layer of skin is called the dermis, and it is the middle layer of the skin, right below the epidermis.