The three factors that influence skin color are The chemical composition of ones skin the biological evolution of skin colour and the effect that environmental surroundings have on skin colour ID: 490375
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Slide1
What is the origin of different skin colours?
The three factors that influence skin color are: The chemical composition of one’s skin, the biological evolution of skin colour and, the effect that environmental surroundings have on skin colour. Slide2
What is the chemical composition of skin colour?
The primary composition of skin’s pigmentation, as well as, the main determent of skin color is melanin.
The more eumelanin in your skin, the darker it will be. People who produce more pheomelanin than eumelanin will tend to have lighter skin with freckles.
When melanocortin 1 receptor is working well, it has the melanocytes convert pheomelanin into eumelanin. If it is not working well, then the pheomelanin builds up.
A tan forms when the melanocytes in skin produce melanin pigmentation in reaction with Ultraviolet
light. Slide3
What does evolution have to do with skin colour?
The biology and evolution of skin color goes back hundreds of years ago, to when the Homo sapiens were covered in hair
.Over time the hair that covered their bodies gradually began to disappear to allow them to sweat, to prevent them from overheating.
Genes that produce dark skin capable of filtering UV radiation spread throughout populations who experienced high levels of UV radiation throughout their lifetime.Hyperpigmentation is caused by an excess production of melanin that can affect the face or the back or the hands
.
Albinism is when a person inherits one or more defective genes that causes them to be unable to produce the sufficient amounts of melanin
.
A more common, non-threatening skin irregularity are birthmarks. They can be cause by overgrowth of blood vessels, melanocytes, smooth muscle, fat, fibroblasts, or keratinocytes.Slide4
How does skin colour adapt to environmental surroundings?
Skin, when subjected to different climates reacts differently and adapts in a particular way to prevent skin damage.
When skin absorbs UV rays from the sun, bodies use that to produce vitamin D.. If someone lives in a region that receives little sunlight, they wouldn’t see much
sunshine. These people would have less melanin in their skin, so naturally they would need less sunshine to make vitamin D.This is why people living in colder place’s skin evolved so that they could obtain a sufficient amount of vitamin D
.
People living in hotter climates closer to the equator, produce more melanin to protect their skin from intense sunlight, creating a darker pigmentSlide5
Conclusion
It is quite relevant that where someone originates from plays a significant role in the colour of his or her skin. Thousands of years ago, the ancestors of human kind experienced drastic climate changes as they moved farther North and farther South. Research shows how their skin slowly adapted to be able to adapt with regard to the strength of the UV light that they were being subjected to. Melanin production fluctuated depending on the strength of the sun resulting in different skin types. Melanin, being the root of skin colour, acts as a vitamin D filter, which is why people with lighter skin have less melanin to make it easier to receive their daily dose of vitamin D. This explains why humans possess variations of skin tones and pigments.