Knowledge of earth system in order to protect, understand and develop research methods.
RNA viruses can copy themselves which is harder for scientists to give an accurate conclusion to solve them.
epithelial tissue can be found lining body cavities, as well as your skin is an epithelial tissue
Answer:
The correct answer is: geography and UV radiation.
Explanation:
Skin variation occurred thanks to evolution, and was driven as a consequence of the geographical location of different populations of humans.
The humans that lived in hot and sunny places, closer to the equator, where much more exposed to the sun's ultraviolet radiation. In order to survive the amount of UV lights that they were exposed to, new humans in those regions were being born with a darker skin tone, which was rich in melanin (a brown pigment that protects us from the sun radiation).
Contrary to these humans that lived in the tropical areas, the humans that populated the areas that were closer to the poles, developed much lighter skin as a result of lower amounts of melanin in their skin. Since sun exposure in the poles is very limited, humans needed to receive as much as they could for the production of Vitamin D, and thus, their skins got lighter and less protected.
Your question has been heard loud and clear.
Lactobacillus is a type of bacteria that mainly occurs in fermented media like yoghurts and curds , but they are mostly present in our body and make up a part of our microbiome by being present in our digestive tracts , genital systems and urinary tracts , doing their job without harming us.
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