Answer:
Keratin: keratin is a type of fibre-protein that can be found in hair, nails, other animal structures, and in our skin.
A really important function of keratin is the one it has in our skin, which consists of protection and holding cells together.
Keratinocytes: keratinocytes, as the "-cytes" suggests, are a type of cell found in our skin, with the function of producing keratin.
A deficiency or problem with these cells can cause a couple of different issues, such as the weakening or growth problems of the diverse amount of things containing significant amounts of keratin.
Hope it helped,
BiologiaMagister