The hair shaft and inner root sheath move together as the hair grows toward the surface: the outer root sheath remains fixed in position.

毛干和内根鞘当到达体表时融合在一起：外根鞘仍然保持在原来的位置。

youdao

The hair shaft and inner root sheath move together as the hair grows toward the surface: the outer root sheath remains fixed in position.

毛干和内根鞘当到达体表时融合在一起：外根鞘仍然保持在原来的位置。

youdao