Florida Cosmetology Licensing ExamChemical ServicesMedium
A cosmetologist is performing a chemical relaxing service using a thio relaxer. Which type of side bond in the hair is primarily broken and then reformed during this process to achieve straight hair?
- AHydrogen bonds
- BSalt bonds
- CDisulfide bonds
- DPeptide bonds
Show answer & explanationAnswer & explanation
Correct answer: C. Disulfide bonds
Thio relaxers, like permanent waves, work by breaking and then reforming the disulfide (sulfur) bonds in the hair's cortex. This chemical alteration changes the hair's natural curl pattern to a straight form.
Why the other options are wrong
- A. Hydrogen bonds are physically broken by water and heat, not chemically by relaxers.
- B. Salt bonds are also broken by changes in pH, but disulfide bonds are the primary target for permanent chemical restructurings.
- D. Peptide bonds (end bonds) link amino acids to form the protein chain and are not broken by relaxers; if they were, the hair would dissolve.
Disulfide Bonds
Strong chemical side bonds in the hair's cortex formed between two sulfur atoms, responsible for the hair's strength and natural curl pattern; they are permanently altered by chemical services like perms and relaxers.
- Strongest of the three side bonds.
- Broken by chemical solutions (reducers) and reformed by neutralizers/oxidizers.
- Determine hair's natural wave and curl pattern.
- Permanent change in hair structure relies on altering these bonds.
Memory trick: Disulfide Drives the Hair Change