suntan
Quick Summary
Suntanning is the process of darkening the skin through exposure to the sun or artificial light. This occurs when skin cells called melanocytes increase their production of melanin, a pigment that darkens the skin. Melanin helps protect the skin from damaging ultraviolet (UV) rays.1234
When skin is overexposed to UVB radiation, it can result in sunburn, an inflammatory reaction ranging from redness to blistering. In response to UV exposure, melanocytes increase melanin production, leading to a tan that offers some protection. While tanning can provide a protective tan, prolonged or excessive exposure to UV radiation can lead to skin disorders, including skin cancer.524
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melanocyte-stimulating hormone…process manifests most noticeably as skin darkening, with exposure to sunlight serving as the stimulus for MSH production and secretion. Similar effects are seen in amphibians, in some fishes, and in reptiles, in which MSH regulates melanin synthesis in cells known as melanophores (a type of chromatophore) and enables the…
Read More…process manifests most noticeably as skin darkening, with exposure to sunlight serving as the stimulus for MSH production and secretion. Similar effects are seen in amphibians, in some fishes, and in reptiles, in which MSH regulates melanin synthesis in cells known as melanophores (a type of chromatophore) and enables the…
Read More- melanocyte
Both suntans and postinflammatory pigmentation result from the overproduction of melanin.
Read MoreBoth suntans and postinflammatory pigmentation result from the overproduction of melanin.
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sunburnWithin days, a protective tan (in mild cases of sunburn) is formed.
Read MoreWithin days, a protective tan (in mild cases of sunburn) is formed.
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- colorationMelanins
…sunlight, human epidermis undergoes gradual tanning with increases in the melanin content, which helps to protect underlying tissues from injurious sun rays.
Read More…sunlight, human epidermis undergoes gradual tanning with increases in the melanin content, which helps to protect underlying tissues from injurious sun rays.
Read More - colorationPhysiological functions
…darkening of the body—for example, tanning in humans. Such melanic shielding protects the tissues of the organism from potentially dangerous levels of ultraviolet radiation. Since the ultraviolet shield need protect only easily damaged cells in the nervous and reproductive systems, it does not necessarily have to lie in the skin…
Read More…darkening of the body—for example, tanning in humans. Such melanic shielding protects the tissues of the organism from potentially dangerous levels of ultraviolet radiation. Since the ultraviolet shield need protect only easily damaged cells in the nervous and reproductive systems, it does not necessarily have to lie in the skin…
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ultraviolet radiationTanning is a natural body defense relying on melanin to help protect the skin from further injury. Melanin is a chemical pigment in the skin that absorbs ultraviolet radiation and limits its penetration into tissues. A suntan occurs when melanin pigments in cells in the…
Read MoreTanning is a natural body defense relying on melanin to help protect the skin from further injury. Melanin is a chemical pigment in the skin that absorbs ultraviolet radiation and limits its penetration into tissues. A suntan occurs when melanin pigments in cells in the…
Read More