The skin carries out three key functions: protecting,, and sensing the world beyond its limits.
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The epidermis is made up mainly of skin cells called keratinocytes. Keratin means (two words)
The English expression for 防水层 is.
Goosebumps appear when people feel cold, andcause hair to stand upright across the body. (two words)
Skin is the largest organ in our body.
A. 对
B. 错
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