Final answer:
The effect of keratin straightening treatments on frizz and curl varies and cannot be given as a specific percentage without more context. These treatments chemically alter hair's keratin by breaking and reforming disulfide bonds.
Step-by-step explanation:
The statement that keratin straightening treatments eliminate up to a certain percentage of frizz and curl is not presented with a specific percentage, making it incomplete and not answerable as a true or false question. Keratin straightening treatments involve chemically altering the structure of the hair. These treatments target the disulfide bonds, which are formed between cysteine units in the hair's keratin protein structure. When these bonds are temporarily broken during the treatment, the hair can be straightened, and when they are reformed, the new straightened shape is maintained.
During perms or chemical straightening processes, chemicals break the disulfide bonds, and the hair is manipulated into the desired curl or straightness before the disulfide bonds are re-established. This process can significantly reduce frizz and curl, although the effectiveness will vary by individual and technique. Therefore, the effect can't be quantified without further context regarding the product or method used.