Skin

Sweat Glands

• Apocrine sweat glands produce a type of secretion that is thick and protein-rich.
• Eccrine sweat glands, on the other hand, produce a sweat response to heat or exercise.

Nail Structure

• The eponychium is located at the base of the nail.
• The nail plate is made of hard keratin.
• The nail matrix generates the nail plate.

Integumentary System

• The hyponychium functions to seal the nail plate to the nail bed.
• The stratum corneum is the layer of the skin sensitive to light touch.
• Pacinian corpuscles function to detect pressure and vibrations.
• The stratum corneum serves as a barrier protecting against physical and chemical injury and infection.

Hair and Sebaceous Glands

• Arrector pili muscles function to cause hair to stand upright.
• Sebaceous glands empty their secretion into the hair follicle.

Vitamin D Synthesis

• The stratum Malpighi is involved in the synthesis of vitamin D3 from precursors in the skin.

Skin Pigmentation

• Melanocytes are the cell type responsible for producing the pigment melanin in the skin.

Epidermal Layers

• The epidermis arises from ectodermal embryonic origin.
• The stratum corneum is composed of flat, dead cells continuously shed.
• The stratum lucidum is present only in very thick skin.
• The stratum basale is the bottom layer, just above the basal lamina, and contains cuboidal to columnar keratinocytes.
• The stratum spinosum is between the stratum granulosum and stratum basale, and contains cells connected by spot desmosomes.
• The stratum granulosum is composed of keratinized stratified squamous epithelium and contains cells with two types of granules, including keratohyaline granules and lamellar granules.

Skin Location

• Thick skin is found on the palms of the hands and soles of the feet.
• Apocrine sweat glands are located in the axillary and anogenital regions.
• Eccrine sweat glands are responsible for producing sweat as a response to heat or exercise.

Other

• Langerhans cells in the epidermis function to detect and respond to pathogens.
• The main component of the keratin layer in the epidermis is dead, keratinized cells.
• Melanocytes in the epidermis produce melanin.