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{%type%} Definitions

WordNet 3.0Copyright Princeton University


Short "hint"

A fibrous scleroprotein that occurs in the outer layer of the skin and in horny tissues such as hair, feathers, nails, and hooves.

Usage examples (38)
  • keratin is the hard protein that hair is made of.
  • The plate of the nail is composed of a substance called keratin, which is produced by amino acids.
  • Hair is made up mostly of a protein called keratin, which is the same material that makes up hooves, claws and fingernails.
  • Protein: As I mentioned above, your hair (and your nails) are made out of the same material called keratin, a protein. for more
Tutoring comment
  • Eating lots of "carotene" (a source of vitamin A found in yellow vegetables) is important for making good quality "keratin" (the protein that aids in building hair and nails).
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