Skin Structure, Types and Basic Skin Care
This section covers Skin Structure, Types and Basic Skin Care. The exam tests the layers of skin, skin functions, skin typing, and a safe basic routine.
Structure and function
The epidermis is the outer layer; its stratum corneum is the barrier, and the basal layer contains melanocytes that produce pigment. The dermis holds collagen, elastin, blood vessels, nerves, hair follicles and sebaceous and sweat glands. The hypodermis is fatty tissue that cushions and insulates. Skin protects against infection and water loss, helps regulate temperature, senses touch, and makes vitamin D. Surface pH is mildly acidic, about 4.5 to 5.5.
Skin types and routine
Normal skin is balanced; dry skin feels tight and may flake; oily skin is shiny with enlarged pores; combination skin has an oily T-zone and drier cheeks; sensitive skin reacts easily. Basic care is cleanse, tone if needed, moisturise and protect with broad-spectrum sunscreen. Match products to the type: gel or foaming cleanser for oily skin, creamy cleanser for dry skin, fragrance-free products for sensitive skin.
Worked example
A client has a shiny forehead and nose but tight, flaky cheeks. This is combination skin. Recommend a mild gel cleanser for the T-zone, a richer moisturiser on the cheeks, and sunscreen daily. Reason: the areas have different sebum levels, so one heavy product for the whole face may clog the T-zone while a light gel may not soothe the cheeks.
Traps
Pores do not open and close. Oily skin still needs a light moisturiser. Hot water and harsh scrubs worsen dryness and sensitivity. Do not diagnose acne or pigmentation; refer.