Texas Class A Barber Written ExamChemical ServicesMedium
A barber is performing a chemical relaxing service using a thio relaxer. Which of the following is the primary chemical action of a thio relaxer on the hair?
- ATo remove sulfur atoms from the disulfide bonds
- BTo swell the hair and open the cuticle layers
- CTo break and reform the peptide bonds in the hair
- DTo break and reform the disulfide bonds in the hair
Show answer & explanationAnswer & explanation
Correct answer: D. To break and reform the disulfide bonds in the hair
Thio relaxers work by breaking the disulfide bonds in the hair's cortex, allowing the hair to be reshaped, and then reforming them in a straighter configuration.
Why the other options are wrong
- A. Removing sulfur atoms is part of the disulfide bond reduction, but 'breaking and reforming' is the more complete action.
- B. Swelling the hair and opening the cuticle is a preparatory action, not the primary chemical action of the relaxer itself.
- C. Peptide bonds form the polypeptide chains, and their breaking would severely damage or dissolve the hair.
Thio Relaxer Action
Thio relaxers chemically straighten hair by breaking and then reforming the hair's disulfide bonds.
- Uses ammonium thioglycolate
- Requires a neutralizer to reform bonds
- Compatible with some permanent waves (carefully)
Memory trick: Thio breaks the 'tie' (disulfide) then 'ties' it back straight.