Definition

1. Noun:
   • A fibrous scleroprotein: Keratin is a tough, insoluble structural protein that forms the main constituent of hair, feathers, nails, horns, claws, hooves, and the outer layer of human skin (the epidermis). It is a key component in many protective and hard tissues in vertebrates.

Usage Examples

• Noun:
  • Hair and nails are primarily composed of keratin.
  • The bird's feathers are strong because they contain keratin.
  • A keratin deficiency can lead to brittle nails and hair.

Advanced Usage

• Keratinization (or Cornification): The biological process by which epithelial cells become filled with keratin protein, die, and form a tough, protective layer.

  • The keratinization of skin cells creates a barrier against the environment.

• Keratinocyte: The predominant cell type in the epidermis, which produces keratin.

  • Keratinocytes migrate to the skin's surface as they produce more keratin.

Variants and Related Words

• Keratinous (adj): Having the nature of or containing keratin.

  • The rhinoceros has a keratinous horn.

• Keratosis (n): A growth of keratin on the skin, such as a callus or wart.

  • Actinic keratosis is a precancerous skin condition caused by sun damage.

Synonyms

• Scleroprotein: A simple protein (like keratin) that is insoluble in water and serves a structural function.
• Fibrous protein: A protein with a long, filamentous structure, providing support and strength.

Related Phrases and Compounds

• Alpha-keratin: The type of keratin found in mammals, constituting hair, nails, horns, and the epidermis.
• Beta-keratin: A tougher form of keratin found in reptiles, birds, and some other animals, constituting scales, feathers, and claws.
• Keratin treatment: A cosmetic hair treatment that uses formulations containing keratin to smooth and straighten hair.
  • She got a keratin treatment to tame her frizzy hair.

Noun

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