Final answer:
The hydroxide relaxer breaks the disulfide bond in hair, converting them to lanthionine bonds and is used to straighten the hair.
Step-by-step explanation:
The hydroxide relaxer breaks the disulfide bond in hair, converting them to lanthionine bonds. This process is used to straighten the hair. By breaking the disulfide bonds, the relaxer allows the hair to be reshaped and straightened. The lanthionine bonds that are formed are weaker and flexible, allowing the hair to be styled into a straighter form.