The Integumentary System pt 5

Secretion: Produce sebum, an oily secretion.

Structure: Flask-shaped glands with short ducts that usually open into hair follicles.

Function: Keeps skin and hair from becoming dry, brittle, and cracked.

Sebaceous Glands

Earwax

cerumen

An oily secretion

sebum

Location: Modified apocrine glands in the external ear canal.

Secretion: Produce cerumen (earwax), a yellow, waxy secretion combined with sebum and dead epithelial cells.

Function: Keeps the eardrum pliable, waterproofs the canal, kills bacteria, and makes guard hairs sticky to block foreign particles

Ceruminous Glands

Nature: Modified apocrine sweat glands that develop in females during pregnancy and lactation.

Function: Produce milk.

Mammary Glands

Two rows of mammary glands found in most mammals; primates typically retain only two

Mammary Ridges

Most common and least dangerous type.

Arises from cells in the stratum basale.

Seldom metastasizes.

Appearance: Small, shiny bump with a central depression and beaded edges.

Basal Cell Carcinoma

Arises from keratinocytes of the stratum spinosum.

Appearance: Raised, reddened, scaly lesion that can form a concave ulcer.

Can metastasize to lymph nodes; recovery is good with early detection.

Commonly found on scalp, ears, lower lip, and back of the hand.

Squamous Cell Carcinoma

Arises from melanocytes.

Least common but most dangerous type.

High risk of metastasis; often fatal if it spreads.

Risk factors include family history, severe sunburns in childhood, and fair skin.

Malignant Melanoma

Involves only the epidermis. Characterized by redness, slight edema, and pain. Heals within days

First-Degree Burn

Involves the epidermis and part of the dermis. Appears red, tan, or white; is blistered and painful. Heals in 2 weeks to several months and may scar

Second-Degree Burn

Involves the entire dermis and often deeper tissues. Often requires skin grafts, fluid replacement, and infection control

Third-Degree Burn