Melanin

Tyrosinase is an enzyme that produces melanin from the amino acid tyrosine. Three different reactions were catalyzed by Tyrosinase; for the first reaction tyrosine is oxidized into DOPA by tyrosinase. Second, tyrosinase oxidizes DOPA to DOPAaquinone and the third reaction tyrosinase oxidizes DOPAquinone to DOPAchrome. The importance and meaning of the oxidation reactions is that DOPAchrome takes the position of a catalyst by DOPAchrome reacting to form melanin and the need catalyst is not…

Introduction Cancer is a disease whereby cells undergo changes that cause them to grow uncontrollably. These changes are caused by gene mutations. Genes are sections of deoxyribonucleic acid (DNA), contained within every cell. Genes control which proteins are synthesised and which cells should be destroyed. Each type of cancer is classified according to the site where the cancer initiated, i.e. the location of initial gene mutation. Malignant melanoma is a skin cancer whereby the cancer…

External Attributions can be used to explain the blue-eyed children’s behaviour during the melanin exercise. According to Plotnik and Kouyoumdjian (2014), ‘External Attributions’ are “explanations of behavior based on the external circumstances or situations.” (P.585) In the case of the blue-eyed girl, her problem with multiplication tables was caused by a situation: the melanin experiment. The melanin experiment and the brown-eyed children’s behavior towards the blue-eyed children would have…

of what I classify as race. Race is not homo sapiens vs other but genetic diversity and groupings within the human race. Genetics affects race in several different factors. The amount of melanin causes a person to look black or white, “Melanin is a complex polymer derived from the amino acid tyrosine. Melanin is responsible for determining skin and hair color and is present in the skin to varying degrees; depending on how much a population has been exposed to the sun historically.” (Mandal)…

The stages of human development can be culturally defined in addition to biologically defined. The biological stages describe when things grown in develop in a human throughout their life span. These stages are for the most part clear and stay pretty true to the ages in when things happen. However in different cultures, they will care for their children in different ways. In different cultures, they experience different upbringings; doing certain things differently because of the way their…

blotches on the body. This disease doesn’t just occur on the skins surfaces, but it can appear on the scalp causing spots of white blotches being seen in hair. Vitiligo occurs when there is damage to the melanocytes, which are cells that produce melanin. Melanin is the pigment…

insulin receptor( insR.) The signals from these neurons are integrated in PVN and LHA to produce orexigenic or anorexigenic signals through the production of CRH (corticotropin-releasing hormone), TRH (thyrotropin-releasing hormone), ORX (orexin), MCH (melanin-concentrating hormone) etc. Figure adopted from Schellekens et al., (2012).303…

unique ability. Pigment causes skin tone for just about every animal, including humans. Unlike people chameleons have different uses for pigment. In a chameleon, hormones effect pigment cells, which leads to their change of colour. The movement of melanin pigment “packets”, contained in melanophores, changes the animal’s shade. A chameleon has many layers of skin. Its main layers are the outer layer, yellow layer, and the scattering layer. Its first layer is see through so the pigments are…

cancer where melanocytesproliferate actively with enhanced accumulation of melaninpigment leading to hyperpigmentation and tumor formation. Up-regulated levels oftyrosinase enzyme appear to be correlated to with greater production and accumulation of melanin which induces skin cancer. Tyrosinase (EC 1.14.18.1) is an oxygen oxidoreductase enzyme involved in vertebrate cutaneous pigmentation, browning of fruits and vegetables, and morphogenesis and fruiting body formation in fungi. It catalyzses…

Enzymes are biological catalysts that speed up chemical reactions and are inexhaustible. They can increase the rate at which reactions occur by up to a factor of 10^19. The material that is being acted on by the enzyme is called a substrate. Enzymes work because they can bind to the transition state better than the substrate, which lowers the activation energy causing the speed of a reaction to accelerate. The enzyme combines with a substrate at the enzymes active site which creates the enzyme…