histology of the integumentary system

1. @OSAMA_Z96

2. 1- Thick Skin
& Sweat Glands
* Component & Characteristics :
1- Epidermis :
A- Stratum corneum (Horny layer).
B- Stratum lucidum.
C- Stratum granulosum.
D- Stratum spinosum.
E- Stratum basale.
2- Dermis :
A- Papillary layer.
B- Reticular layer.
3- Sweat gland (coiled tubular).
4- Sweat gland duct.
5- Hypodermis.
* Function :
- Skin :
Sensation, protection, and temperature control.
* Histopathological Lesion :
- Actinic keratosis.

4. 2- Hairy Skin
* Component & Characteristics :
1- Epidermis.
2- Dermis.
3- Arrector pili muscle.
4- Sebaceous glands.
5- Sweat gland.
* Function :
- Sebaceous glands :
Secretion of the sebum.
* Histopathological Lesion :
- Ectopic sebaceous glands.

6. 2- Hairy Skin
* Component & Characteristics :
1- Epidermis (Keratinized stratified squamous epithelium).
2- Epidermal ridge.
3- Dermal papilla.
4- Hair medulla.
5- Hair cortex.
6- Hair cuticle.
7- Inner root sheath.
8- Outer root sheath.
9- Hair follicle.
10- Arrector pili muscle.
11- Sebaceous glands.
12- Sweat glands.
* Function :
- Hair follicle.
Regulation of hair growth.
* Histopathological Lesion :
- Hair follicle nevus.

8. 3- Hair Root
* Component & Characteristics :
1- Hair medulla.
2- Hair cortex.
3- Hair cuticle.
4- Inner root sheath :
A- Inner cuticular layer.
B- Huxley layer.
C- Henle’s layer.
5- Outer root sheath :
Extension of stratum basale & stratum spinosum.
6- Glassy membrane :
Thickened epidermis basement membrane.
7- Connective tissue sheath.
* Function :
- Fix the hair in the dermis.
* Histopathological Lesion :
- Alopecia.

10. 4- Tactile Receptors
* Component & Characteristics :
1- Epidermis :
A- Stratum corneum.
B- Stratum granulosum (Big granules - Brown).
C- Stratum spinosum.
D- Stratum basale.
2- Epidermal ridge.
3- Dermal papilla.
4- Dermis.
5- Meissner’s corpuscle (Tactile).
* Function :
- Sensation of crude touch & light pressure.
* Histopathological Lesion :
1- Atrophic ulcers.
2- The 2nd & 3rd degree burns.