An Inch of Skin!
What do you think you’d find in one
square inch of human skin?
Write down a list of all the things that
you think you might find.
Think small. Very, very small.
In each square inch of human skin:
(These are out of order. Try to guess at some of them!)
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How many hairs?
How many cells?
How many sweat glands?
How many oil glands?
How many blood vessels?
How many nerves?
How many nerve endings?
How many heat sensors?
How many cold sensors?
How many pain sensors
How many touch sensors?
How many bacteria?
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78 yards (70 meters)
650
9,500,000
160-165
19,500
13
19 yards (17 meters)
32,000,000
78
1,300
65
95-100
The correct order!
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




How many hairs?
How many cells?
How many sweat glands?
How many oil glands?
How many blood vessels?
How many nerves?
How many nerve endings?
How many heat sensors?
How many cold sensors?
How many pain sensors
How many touch sensors?
How many bacteria?
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65 hairs
9,500,000 cells
650 sweat glands
95-100 oil glands
19 yards of blood vessels
78 yards of nerves
19,500 nerve endings
78 heat sensors
13 cold sensors
1,300 pain sensors
160-165 touch sensors
32,000,000 bacteria
The correct order!












How many hairs?
How many cells?
How many sweat glands?
How many oil glands?
How many blood vessels?
How many nerves?
How many nerve endings?
How many heat sensors?
How many cold sensors?
How many pain sensors
How many touch sensors?
How many bacteria?












65 hairs
9,500,000 cells
650 sweat glands
95-100 oil glands
19 yards of blood vessels
78 yards of nerves
19,500 nerve endings
78 heat sensors
13 cold sensors
1,300 pain sensors
160-165 touch sensors
32,000,000 bacteria