Search results
Results from the WOW.Com Content Network
Melanocytes are melanin-producing neural crest-derived [3] cells located in the bottom layer (the stratum basale) of the skin's epidermis, the middle layer of the eye (the uvea), [4] the inner ear, [5] vaginal epithelium, [6] meninges, [7] bones, [8] and heart found in many mammals and birds. [9] Melanin is a dark pigment primarily responsible ...
Hyperpigmentation can be diffuse or focal, affecting such areas as the face and the back of the hands. Melanin is produced by melanocytes at the lower layer of the epidermis . Melanin is a class of pigment responsible for producing color in the body in places such as the eyes, skin, and hair.
They have a dominant gene that causes hyperpigmentation (Fibromelanosis), making the chicken entirely black; including feathers, beak, and internal organs. Melanism in feral rock doves are actually quite common,to some extent, especially if the area is abundant with the species. The amount of pigmentation is varied, from a slight darker ...
Biological pigments, also known simply as pigments or biochromes, [1] are substances produced by living organisms that have a color resulting from selective color absorption. Biological pigments include plant pigments and flower pigments.
Poikiloderma is a skin condition that consists of areas of hypopigmentation, hyperpigmentation, telangiectasias and atrophy. Poikiloderma of Civatte is most frequently seen on the chest or the neck, characterized by red colored pigment on the skin that is commonly associated with sun damage.
[6] Melasma is thought to be the stimulation of melanocytes (cells in the dermal layer, which transfer the pigment melanin to the keratinocytes of skin) when the skin is exposed to ultraviolet light from the sun. Small amounts of sun exposure can make melasma return to the skin after it has faded, which is why people with melasma often get it ...
Having six or more café au lait spots greater than 5 mm in diameter before puberty, or greater than 15 mm in diameter after puberty, is a diagnostic feature of neurofibromatosis type I (NF-1), but other features are required to diagnose NF-1. [2] Familial multiple cafe-au-lait spots have been observed without an NF-1 diagnosis. [9] Noonan syndrome
Freckles are clusters of concentrated melaninized cells which are most easily visible on people with a fair complexion.Freckles do not have an increased number of the melanin-producing cells, or melanocytes, but instead have melanocytes that overproduce melanin granules (melanosomes) changing the coloration of the outer skin cells (keratinocytes).