melanin
(noun)
Any of a group of naturally occurring dark pigments responsible for the color of skin.
Examples of melanin in the following topics:
-
Skin Color
- Skin color is determined largely by the amount of melanin pigment produced by melanocytes in the skin.
- Skin color is largely determined by a pigment called melanin but other things are involved.
- The most abundant type of melanin is called eumelanin.
- If a person is unable to produce melanin, they have a condition called albinism.
- Besides melanin, other factors play a role in general or local skin color.
-
Albinism
- Albinism is a congenital disorder characterized by the complete or partial absence of pigment in the skin, hair, and eyes due to he absence of or defect in an enzyme involved in the production of melanin .
- All alterations, however, lead to changes in melanin production in the body.
- Individuals with albinism posses melanocytes, the melanin-producing cell of the skin, but their melanocytes are unable to produce melanin.
-
Nails
- This portion of the nail does not have any melanocytes, or melanin producing cells.
- The nail bed contains the blood vessels, nerves, and melanocytes, or melanin-producing cells.
-
Development of the Integumentary System
- Melanoblasts that will form melanocytes migrate with neural crests cells to the epithelium and begin producing melanin prior to birth.
-
Race
- In modern society, some people who consider themselves "white" actually have more melanin (a pigment that determines skin color) in their skin than other people who identify as "black. " In some countries, such as Brazil, class is more important than skin color in determining racial categorization.
- People with high levels of melanin in their skin may consider themselves "white" if they enjoy a middle-class lifestyle.
- On the other hand, someone with low levels of melanin in their skin might be assigned the identity of "black" if they have little education or money.
-
Vitiligo
- Vitiligo is a disorder characterized by patchy loss of skin pigmentation due to the immune system attacking melanocytes, the melanin-producing cells of the skin .
-
Overview of the Body's Surface
- Skin Structure.Skin has mesodermal cells, pigmentation, or melanin provided by melanocytes, which absorb some of the potentially dangerous ultraviolet radiation (UV) in sunlight.
-
Horner's Syndrome
- This happens because a lack of sympathetic stimulation in childhood interferes with melanin pigmentation of the melanocytes of the iris.
-
Basal Ganglia
- The most notable are Parkinson's disease, which involves degeneration of the melanin-pigmented dopamine-producing cells in the substantia nigra pars compacta (SNc), and Huntington's disease, which primarily involves damage to the striatum.
-
Nonrandom Mating and Environmental Variance
- The American Robin may practice assortative mating on plumage color, a melanin based trait, and mate with other robins who have the most similar shade of color.