MELANIN

mĕlˈənĭn, water-insoluble polymer of various compounds derived from the amino acid tyrosine. It is one of two pigments found in human skin and hair and adds brown to skin color; the other pigment is carotene, which contributes yellow coloring. The synthesis of melanin reactions is catalyzed by the enzyme tyrosinase; an inherited lack of tyrosinase activity results in one of the forms of albinism. Tyrosinase is found in only one specialized type of cell, the melanocyte, and in this cell melanin is found in membrane-bound bodies called melanosomes. Melanosomes can be transferred from their site of synthesis in the melanocytes to other cell types. The various hues and degrees of pigmentation found in the skin of human beings are directly related to the number, size, and distribution of melanosomes within the melanocytes and other cells. Besides it role in pigmentation, melanin, which absorbs ultraviolet light, plays a protective role when skin is exposed to the damaging rays of the sun (see sunburn; skin cancer).

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The Columbia Encyclopedia, Sixth Edition Copyright© 2004, Columbia University Press. Licensed from Lernout & Hauspie Speech Products N.V. All rights reserved.

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Questia Books and Articles on: Melanin
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books on: Melanin  - 426 results

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1.
Encyclopedia of Family Health - Vol. 9
Book by David B. Jacoby, Robert M. Youngson; Marshall Cavendish, 2005
Subjects: Health--Encyclopedias, Medicine, Popular--Encyclopedias
Melanin Questions and Answers I am fair-skinned...respond more slowly and take longer to form melanin, the pigment that darkens the skin. I...illness, so a doctor should be consulted. Melanin disorders are quite uncommon, are rarely...
2.
Encyclopedia of Life Sciences - Vol. 10
Book by Anne O'Daly; Marshall Cavendish, 2004
Subjects: Biology--Encyclopedias, Life Sciences--Encyclopedias
...is a layer of melanophores. When the melanin granules are fully dispersed, the chameleon...resulting from the uneven distribution of melanin- producing melanocytes throughout the...which animals must obtain from plants. Melanin Among the amino acids produced by metabolic...
3.
Muslims on the Americanization Path?
Book by Yvonne Yazbeck Haddad, John L. Esposito; Oxford University Press, 2000
Subjects: Islam--United States, Muslims--United States
...Afrocentrists began to use the con- cept of melanin (see following note). 30. Frances...popular work to introduce the concept of melanin into the Afrocentric discourse. Legrand Cleggs article Melanin: The Key to Black Genetic Superiority...
4.
100 Most Popular Scientists for Young Adults: Biographical Sketches and Professional Paths
Book by Kendall Haven, Donna Clark; Libraries Unlimited, 1999
Subjects: Science--History--20th Century, Scientists--Biography
...to research cells that contain a dark pigment called melanin. Melanin determines human skin color. People with dark skin...as African Americans, usually have large amounts of melanin in their skin. Skin moles contain concentrations of...
5.
Coretta Scott King Award Books: Using Great Literature with Children and Young Adults
Book by Claire Gatrell Stephens; Libraries Unlimited, 2000
Subjects: African American Authors--Biography, African American Illustrators--Biography, African Americans In Literature--Study And Teaching, American Literature--African American Authors--Bibliography, American Literature--African American Authors--Study And Teaching, Children's Literature, American--Bibliography, Children's Literature, American--Study And Teaching, Children--United States--Books And Reading, Coretta Scott King Award, Young Adult Literature, American--Bibliography, Young Adult Literature, American--Study And Teaching
...think. E. C. insists that Melanin try to get to know Kristen, and as he does so Melanin has some reali- zations...conflicts. By the storys end, Melanin knows he will probably never...its controversial issues. Melanins jour- ney is thought...
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journal articles on: Melanin  - 135 results

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1.
Melanin on the Margins: Advertising and the Cultural Politics of Fair/light/white Beauty in India
Journal article by Radhika Parameswaran, Kavitha Cardoza; Journalism and Communication Monographs, Vol. 11, 2009
Subjects: Colleges & universities, Conventions, Economic reform, Education, Field study, Middle class, Politics, Sex crimes, Television advertising, Upward mobility
Melanin on the Margins: Advertising and the Cultural...endured as a woman imprisoned within the melanin of her dark skin: Despite being revered...consumers that they can inhibit or diminish melanin production and defend facial skin against...
2.
Conserved Function of Medaka Pink-eyed Dilution in Melanin Synthesis and Its Divergent Transcriptional Regulation in Gonads among Vertebrates
Journal article by Shoji Fukamachi, Shuichi Asakawa, Yuko Wakamatsu, Nobuyoshi Shimizu; Genetics, Vol. 168, 2004
Subjects: Amino acids, Deoxyribonucleic acid--DNA, Genes, Genomics, Vertebrates
...Function of Medaka Pink-eyed Dilution in Melanin Synthesis and Its Divergent Transcriptional...albinism (OCA) in mammals; i.e., melanin deposition is strongly suppressed over...from the i-locus mutants that lack the melanin-synthesizing enzyme, tyrosinase (KOGA...
3.
Elejalde Syndrome: Clinical and Histopathological Findings in an Egyptian Male
Journal article by H. H. Afifi, M. S. Zaki, G. Y. El-Kamah, M. El-Darouti; Genetic Counseling, Vol. 18, 2007
Subjects: Melanins
...Skin tanning results from defective melanin transport with consequent heavily pigmented...bases into 4 groups: 1) disorders of melanin synthesis in the melanosome, 2) disorders...revealed irregularly distributed large melanin clumps characteristic of ES confirmed...
4.
Melanotic Mutants in Drosophila: Pathways and Phenotypes
Journal article by Svetlana Minakhina, Ruth Steward; Genetics, Vol. 174, 2006
Subjects: Blood, DNA-Binding Proteins, Drosophila Proteins, Genetic engineering, Genotype & phenotype, Immune system, Melanins, Nuclear Proteins, Phosphoproteins, Protease inhibitors, Tissue, Transcription Factors, cactus protein, Drosophila, dl (Dorsal) protein, Drosophila
5.
Understanding Essentialism as Fundamental: The Centered African Perspective on the Nature of Prototypical Human Nature: Cosmological Ka (Spirit)
Journal article by Daudi Ajani Ya Azibo; The Western Journal of Black Studies, Vol. 35, 2011
Subjects: Black studies, Blacks--Study and teaching, Essentialism (Philosophy)--Analysis, Human nature, Life force, Social constructionism, Vital force
...this process involve neuromelanin and melanin, i.e., biological blackness, in...prototype is certainly not happenchance. Melanin is one of those significant things put...this and screens the scientifically sound melanin research from the unsound. King (1977...
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magazine articles on: Melanin  - 136 results

       More magazine Results: 1-10 11-20 21-30 31-40 41-50 >>  
 
1.
Dark Power: Pigment Seems to Put Radiation to Good Use
Magazine article by D. Castelvecchi; Science News, Vol. 171, May 26, 2007
Subjects: Casadevall, Arturo--Research, Fungi--Research, Gamma rays--Research, Melanin--Research
...which produced no melanin, grew at a normal pace...took a closer look at melanin. In one experiment...four-fold increase in melanins ability to catalyze...metabolism. They also tested melanins response to gamma rays...gamma rays kick some melanin electrons into excited...
2.
UV Blocker: Lotion Yields Protective Tan in Fair-Skinned Mice
Magazine article by N. Seppa; Science News, Vol. 170, September 23, 2006
Subjects: DNA damage--Control, Skin care products--Research, Sun exposure--Care and treatment, Suntan lotions--Research
...stimulates production of the skin pigment melanin induces a deep tan in specially bred laboratory...Further tests showed that the additional melanin protected the mice against UV-induced...molecule thats instrumental in producing melanin. Normally, melanin manufacture requires...
3.
Genes, Greens, and Oils: the Causes, Prevention, and Natural Treatment of Amd
Magazine article by Lylas G. Mogk, Marja Mogk; The Saturday Evening Post, Vol. 276, July 2004
Subjects: Blood vessels, Dietary supplements, Macular degeneration, Smoking cessation, Vegetables
...lighter our eyes, the less protective melanin (or pigment) they have to protect us...abnormal chunks of metabolized waste. Melanin, the substance that gives eyes their...colored eyes or fair skin have much less melanin than people with dark eyes. Light-colored...
4.
Feeling the Burn
Magazine article by Jay Withgott; Natural History, Vol. 110, July 2001
Subjects: Ozone, Research, Sun, Ultraviolet radiation
...B. In many animals, pigments such as melanin serve to block ultraviolet light; a number...instance, produce eggs equipped with melanin. And in many microorganisms as well as...radiation-intercepting compounds. Extra melanin is deployed in human skin exposed to the...
5.
FYI
Magazine article by Cecilia Wessner; Popular Science, Vol. 250, January 1997
...Ophthalmology. It all depends on the amount of melanin, a dark pigment, in the iris-the colored...People with brown eyes have the most melanin in their irises, those with hazel eyes...even less. When a baby is born, the melanin pigment is concentrated in the folds of...
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newspaper articles on: Melanin  - 387 results

       More newspaper Results: 1-10 11-20 21-30 31-40 41-50 >>  
 
1.
Has Your Holiday Wrecked Your Skin?
Newspaper article; The Daily Mail (London, England), September 22, 2008
Subjects: Melanin, Toiletries industry
...the sun triggers excess production of melanin, the skins colour pigment, which can...Procysteine, an ingredient that acts on melanin production and evens skin tone. If youre...which is gently to block the production of melanin and new pigmentation, as well as helping...
2.
Forever YOUNG; Slapping on Anti-Wrinkle Creams May Not Be the Answer to Looking Younger. Researchers Now Say the Real Secret to Holding Back the Years Is Glowing Skin. Here's How to Ensure Your Face Looks Radiant for Longer
Newspaper article; The Mirror (London, England), February 9, 2010
Subjects: Dermatologic agents, Dermatology--Formulae, receipts, prescriptions, Melanin, Skin care, Skin care products, Skin creams, Skin--Care and treatment
...the condition of their skin. The reason is that as we age, melanin and haemoglobin become more unevenly spread throughout the...B) can offer a more long-term solution as this moderates melanin, evening out blotches and age spots and balancing skin tone...
3.
Would You Take the Skin Dye Pill? CHANGING YOUR PIGMENTATION AND EYE COLOUR BY SWALLOWING A TABLET COULD SOON BE A REALITY
Newspaper article; The Evening Standard (London, England), March 15, 2007
...mostly influenced by a dark pigment called melanin. But previously it was thought that tanning...DNA. This was thought to activate the melanin-producing centres within the cells...a long-known hormone to try to boost melanin production. However, this tends to work...
4.
Beauty Today: The Whiter, the Better?
Newspaper article; Manila Bulletin, December 9, 2007
...skin tone, meaning the Japanese have low melanin and skin redness susceptibility. Their...have the darkest skin tone, thus high melanin content and skin redness. Because of...bacterium and many chemicals. "The pigment melanin is found throughout the three layers...
5.
All-Over Tan? Forget It; an Even Glow Is Impossible Because Your Skin Varies in Thickness
Newspaper article; The Daily Mail (London, England), August 5, 2010
...than on the back. It also contains less melanin - the pigment that darkens the skin...has more sebaceous glands which produce melanin quickly. BACK The skin on the back...the back due to thicker skin and less melanin. ARMS The outsides of the arms go brown...
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encyclopedia articles on: Melanin  - 9 results

       More encyclopedia Results: 1-9 >>  
 
1.
Melanin
Encyclopedia article; The Columbia Encyclopedia, Sixth Edition, 2009
MELANIN mel nin, water-insoluble polymer of...contributes yellow coloring. The synthesis of melanin reactions is catalyzed by the enzyme tyrosinase...cell, the melanocyte, and in this cell melanin is found in membrane-bound bodies called...
2.
Pigmentation
Encyclopedia article; The Columbia Encyclopedia, Sixth Edition, 2009
...hemoglobin, the carotenes, the melanins (black and brown), and guanine...primarily on the amount of melanin present. The presence of hemoglobin...high local concentrations of melanin; albinism by a lack of melanin; and some birthmarks, e...
3.
Sunburn
Encyclopedia article; The Columbia Encyclopedia, Sixth Edition, 2009
...a process that can go wrong and result in skin cancer ). At the same time, the production of melanin increases, darkening the skin. Melanin, the pigment that gives skin its color, acts as a barrier to further damage by absorbing ultraviolet...
4.
Skin Cancer
Encyclopedia article; The Columbia Encyclopedia, Sixth Edition, 2009
...melanomas are also seen in dark-skinned people. Melanomas arise in melanocytes, the melanin -containing cells of the epidermal layer of the skin. Melanin is the pigment that gives skin color and that helps to protect the skin from sun damage...
5.
Urinalysis
Encyclopedia article; The Columbia Encyclopedia, Sixth Edition, 2009
...remove waste substances from the blood plasma per unit of time. The urine of patients with melanotic cancer will often contain melanin, a skin pigment. A diagnosis of drug addiction may be confirmed by the presence of specific chemical substances in the urine...
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