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The Importance of keratin in the human body
Keratin is an extremely strong protein which is
a major component in skin, hair, teeth and
nails. It is also present in fur, feathers, horns,
nails, claws, scales, hooves and whale baleen.
It provides a protective layer that helps to
prevent the passage of bacteria, viruses and Most of t he Keratin
other organisms into the body. people react with is
actually dead ­ such
It provides your body with a durable `overcoat' as hair, skin and
that protects deeper cells from damage, nails.
infection and drying out.…read more

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Keratin forms in cells known as keratinocytes located in the
lower parts of an animal's dermal layers.
The process it is formed in is known as keratinization, in which
the keratinocytes make and store keratin within a cell's
As the cells age, newer cells begin to push the keratinocytes
Most of the cell's structures, including the nucleus, die during
this process, leaving only a flattened layer of keratin.…read more

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Keratin molecules supercoil to form very stable superhelixes
which then form quaternary structures.
The chains are antiparallel with alternating C N orientation.
In addition to the relatively weak intra and intermolecular
hydrogen bonds, keratins have large amounts of cysteine
which is required for the formation of disulphide bridges.
Disulphide bridges confer extra strength and rigidity to the
structure by adding permanent cross links. Disulphide bonding
contributes to the insolubility of keratins.…read more

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More flexible keratins (such as those found in hair) have a
lower number of disulphide bridges than harder keratins.
Hair and other -keratins consist of -helically coiled
single protein strands with regular intra-chain hydrogen
bonding. These are then further twisted to form
superhelical ropes.
-keratins comprise -pleated sheets twisted together
and hardened by disulphide bridges.…read more

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Keratin helps protect the epithelial cells from damage
and stress possibly fatal to the cell.
It also plays a part in waterproofing skin and maintaining
elasticity and firmness in it.
Strengthens hair and toughens nails and other bony
structures such as horns, hooves, beaks and even
Helps with cell signalling and aids apoptosis.…read more

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