Bio 4.1 Positions and tissue types of Dermis

Epidermis

• Outermost layer of the skin.

• Made of epithelial tissue.

• Provides protection and forms a barrier against the outside environment.

Dermis

• Located directly below the epidermis.

• Contains blood vessels, nerves, hair follicles, sweat glands, and other structures.

• Provides strength and support to the skin.

 Hypodermis (subcutaneous membrane/superficial fascia)

• Located below the dermis.

• Connects the skin to underlying tissues.

• Contains mainly adipose and connective tissue.

• Helps with insulation, cushioning, and energy storage.

Epidermis Stgrctures

• Keratinized stratified squamous epithelium

• Main function: kreatin is armor,  protection.

Dermis

• Mainly connective tissue.

• Papillary layer: Areolar connective tissue.

• Reticular layer: Dense irregular connective tissue.

• Provides strength, support, and elasticity.

Hypodermis (subcutaneous layer)

• Mainly areolar connective tissue and adipose tissue.

• Provides insulation, cushioning, and energy storage.

Keratinocytes

• Location: Found throughout the epidermis; most abundant in the epidermis.

• Function: Produce keratin, which helps protect the skin and makes it strong and waterproof.

Melanocytes

• Location: Mainly found in the stratum basale, the deepest layer of the epidermis.

• Function: Produce melanin, the pigment that gives skin its color and helps protect cells from UV radiation.

Thick Skin

• Location: Palms of the hands and soles of the feet.

• Contains a thick epidermis and has no hair follicles or sebaceous glands.

Thin Skin

• Location: Covers most of the rest of the body.

• Has a thinner epidermis and generally contains hair follicles and sebaceous glands.