Muaj cov qog sebaceous ntawm tus dev daim tawv nqaij, thiab cov qog sebaceous secrete sebum, uas tsim ib txheej ntawm sebum ntawm daim tawv nqaij los tiv thaiv daim tawv nqaij. Kev da dej tsis tu ncua yuav rhuav tshem cov sebum txheej, uas thaum kawg yuav ua rau txo qis ntawm daim tawv nqaij tiv thaiv thiab kis kab mob thiab qhov txhab. Feem ntau, cov menyuam dev tuaj yeem ntxuav ib zaug ib lub lim tiam, thiab cov dev loj tuaj yeem ntxuav txhua 2 lub lis piam.
