Integumentary System: Skin and Hair Anatomy

This set of flashcards covers key vocabulary and concepts related to the anatomy and functions of the skin and hair as discussed in the lecture notes.

Melanocytes

Cells in the deepest layer of the epidermis that produce melanin, protecting DNA from UV damage.

Intra epidermal Macrophages (Dendritic Cells)

Cells synthesized in bone marrow that migrate to the epidermis to protect against infection.

Tactile Epithelium Cells (Merkel Cells)

Encapsulated nerve discs in the skin that detect touch.

Stratum Corneum

The outermost layer of skin that is 25-35 cells thick, with no cellular organelles and continuously shed and replaced.

Cholecalciferol

A hormone produced by skin cells when exposed to UV light, which is converted to Calcitriol in the kidneys.

Calcitriol

The active form of Vitamin D₂ that enhances calcium absorption in the ileum of the small intestine.

Growth Stage of Hair

The phase in which hair grows for 2-6 years.

Regression Stage of Hair

A phase where the hair follicle atrophies and hair stops growing for 2-3 weeks.

Resting Stage of Hair

A phase that lasts for 3 months before the hair cycle repeats.

Lanugo Hair

Fine hairs that cover the fetus during utero development.

Vellus Hairs

Fine hairs that replace lanugo hairs at birth.

Papillary Dermis

The layer of the dermis closest to the stratum basal of the epidermis, containing areolar connective tissue.

Dermal Papillae

Projections in the papillary dermis that contain blood vessels and nerve endings.

Meissner's Corpuscles

Touch receptors located in the dermal papillae.

Free Nerve Endings

Nerve endings in the skin responsible for sensations of pain, warmth, cold, and itch.