The inner or epidermic coat of the

hair follicle The hair follicle is an organ found in mammalian skin. It resides in the dermal layer of the skin and is made up of 20 different cell types, each with distinct functions. The hair follicle regulates hair growth via a complex interaction betwe ...

is closely adherent to the root of the hair, and consists of two strata named respectively the outer and inner root sheaths.

Outer root sheath

The outer root sheath corresponds with the

stratum mucosum The Malpighian layer (''stratum mucosum'' or ''stratum malpighii'') of the epidermis, the outermost layer of the skin, is generally defined as both the stratum basale (basal layer) and the thicker stratum spinosum (spinous layer/prickle cell layer ...

( stratum germinativum and

stratum spinosum The stratum spinosum (or spinous layer/prickle cell layer) is a layer of the epidermis found between the stratum granulosum and stratum basale. This layer is composed of polyhedral keratinocytes. These are joined with desmosomes. Their spiny ( ...

) of the

epidermis The epidermis is the outermost of the three layers that comprise the skin, the inner layers being the dermis and Subcutaneous tissue, hypodermis. The epidermis layer provides a barrier to infection from environmental pathogens and regulates the ...

, and resembles it in the rounded form and soft character of its cells; at the bottom of the

these cells become continuous with those of the root of the hair.

Inner root sheath

The inner root sheath (IRS) consists of # a delicate cuticle next the hair, composed of a single layer of imbricated scales with atrophied nuclei; # Huxley's layer # Henle's layer The term "trichilemmal" refers to the outer root sheath. The IRS functions to mould, adhere, as well as participate in the keratinization of growing hair.

References

External links

* * {{Integumentary system Hair anatomy