Hair, dyed

Photomicrograph of dyed human hair. Bleaching removes pigment from the hair and can give the hair a characteristic yellow cast. The cortical cell margins may become more prominent and cortical fusi may develop. In addition, harsh or repeated treatments can make the hair shaft brittle, and the scales will appear disturbed.

Image courtesy of Microscopy of Hair Part 1: A Practical Guide and Manual for Human Hairs; Forensic Science Communications.