It has long been known that the thickness of the epidermis varies around the body. For example, skin is thicker on the soles but thinner on the ears. However, the mechanism for maintaining the relative thickness of the outer skin, or epidermis, has been largely unknown.
Now, the research group, led by Professor Tomomi Nemoto of the university's Research Institute for Electronic Science, has established a new method for three-dimensional, real-time observation of the deep structure of the skin in living mice using advanced microscopy technology.
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The team's analysis revealed for the first time that in thicker skin, basal cells divide obliquely with high frequency, whereas for basal cells in thin skin -- such as the back and ears -- divisions in the basement membrane were mostly parallel. By analyzing divisional direction three-dimensionally, correlations were found between the thickness of the epidermis and the frequency of oblique division with regard to the basement membrane.
In case you always wondered.
(Score: 2) by DannyB on Thursday October 20 2016, @03:59PM
The answer to "Why" is your choice of:
1. adaptive evolution
2. because it was created that way, or simulation hypothesis if you prefer
The more interesting question is "How". When a fertilized cell begins dividing, it starts growing in different directions non uniformly. After many generations of cell division the organism begins to exhibit two arms, two legs, etc.
The lower I set my standards the more accomplishments I have.