Skin Anatomy and Physiology Quiz

Skin Anatomy and Physiology

• Pores are tiny openings on the skin's surface, facilitating sweat and oil secretion.
• Sebaceous glands secrete sebum, an oily substance that conditions the skin and hair.
• Epidermis is the outermost skin layer, composed primarily of squamous epithelium, and includes the stratum corneum, the protective outer layer of flattened, keratinized cells.
• Dermis, the middle layer of skin, supports blood vessels, nerves, and glands.
• Subcutaneous layer is the innermost layer, containing fat tissue that insulates and cushions the body.
• Adipocytes are fat cells that store energy and help insulate the body.

Skin Pigmentation and Conditions

• Melanin is the skin pigment produced by melanocytes; two types exist: eumelanin (brown-black) and pheomelanin (red-yellow).
• Albino individuals have a deficiency in melanin, leading to lighter skin and increased sensitivity to sunlight.
• Vitiligo is characterized by the loss of skin pigment, often in an autoimmune context, leading to milk-white patches.

Skin Lesions and Diseases

• Crust is formed from dried serum and cellular debris, seen in conditions like eczema and impetigo.
• Cyst is a closed sac containing fluid or semisolid material; examples include pilonidal and sebaceous cysts.
• Erosion represents a superficial loss of epidermis without scarring, unlike ulcers, which are deeper open sores.
• Alopecia refers to hair loss that can be caused by genetics, disease, or treatment (e.g., chemotherapy).
• Impetigo is a contagious bacterial skin infection resulting in vesicles and crusted lesions, commonly treated with antibiotics.

Tumors and Cancer Types

• Basal cell carcinoma is the most common skin cancer, characterized by slow growth, often appearing on sun-exposed areas; it rarely metastasizes.
• Squamous cell carcinoma arises from squamous epithelium and may develop in diverse locations, including the mouth and lungs; associated with sun damage.
• Malignant melanoma originates from melanocytes and is highly aggressive, often linked to UV exposure; irregular borders and changes in color signify its presence.

Inflammation and Allergic Reactions

• Eczema (atopic dermatitis) causes erythematous, itchy lesions, more prevalent with a family history of allergies.
• Scabies causes severe itching due to a parasitic infection, treated with topical creams.
• Urticaria (hives) is an acute allergic reaction where red, swollen wheals appear on the skin, driven by histamine release.

Skin Structures and Their Functions

• Hair follicles are the sacs from which hair grows, embedded in the dermis.
• Cuticles protect the base and sides of nails, essential for nail health.
• Keratin is a hard protein found in the epidermis, hair, and nails, providing strength and resilience to skin and structures.

Skin-Related Terms and Suffixes

• -derm, as in dermatology, relates to skin.
• -cyte denotes cells (e.g., adipocyte for fat cells).
• -oma indicates tumor (e.g., melanoma, keloid).

Common Skin Conditions

• Psoriasis causes red, itchy, scaly plaques often triggered by stress or injury.
• Burns are injuries caused by heat, categorized into first-degree (superficial) to third-degree (full thickness).
• Cellulitis presents as a diffuse skin infection marked by redness, heat, and swelling, requiring prompt antibiotic treatment.

Physiological Responses and Skin Care

• Diaphorese denotes profuse sweating and can indicate various physiological states.
• Pruritus, or itching, arises from irritants acting on skin nerves and is common in conditions like dermatitis.
• Keloids are thickened scars resulting from excess collagen formation, often seen after skin trauma.

Comprehensive Understanding

• Understanding skin structures, lesions, diseases, and their treatments is vital for effective dermatological practice and patient care.