California Cosmetology Written ExamChemical Texture ServicesEasy
A client receives a wet set and roller style but notices the curl pattern relaxes within hours in humid weather. Which bond is responsible for this temporary change, being broken by water and reformed as the hair dries?
- AHydrogen bond
- BAmino bond
- CDisulfide bond
- DPeptide bond
Show answer & explanationAnswer & explanation
Correct answer: A. Hydrogen bond
Hydrogen bonds are weak, temporary physical bonds that break easily with water and heat and reform as hair dries, explaining why wet-set curls revert in humidity.
Why the other options are wrong
- B. Amino bond is not a recognized hair bond classification.
- C. Disulfide bonds require chemical reducing agents to break, not water.
- D. Peptide bonds are unaffected by water or styling.
Hydrogen Bond
A weak, temporary physical bond in the hair cortex broken by water or heat and reformed when hair dries or cools.
- Represents about 1/3 of hair's overall strength
- Broken during shampooing/wet styling
- Reforms during drying/cooling, causing temporary style
Memory trick: 'Hydrogen = Humidity-hater, breaks in water'