Plucking hair hurts because it stimulates sensitive nerve endings located at the base of the hair follicle.
Here's a more detailed explanation:
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Hair Follicle Structure: Each hair grows from a root located in a follicle within the dermis layer of the skin.
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Hair Root Plexus: The base of each hair follicle is surrounded by a network of sensory nerve fibers known as the hair root plexus. These plexuses are highly sensitive to touch and movement.
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The Plucking Process: When you pluck a hair, you're essentially pulling the hair shaft and its root out of the follicle. This action mechanically stimulates and often damages the surrounding hair root plexus.
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Signal Transmission: The stimulated nerve endings send pain signals to the brain, resulting in the sensation of pain.
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Why Cutting Hair Doesn't Hurt: The hair shaft itself is made of dead cells and contains no nerves. Therefore, cutting the hair above the skin's surface doesn't stimulate any nerve endings and is painless.
In summary, plucking a hair is painful because it activates the sensitive nerve network at the base of the hair follicle, while cutting hair is painless because the hair shaft lacks nerves.
