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Esthetician (NIC Theory Exam) · Scientific Concepts

Esthetician (NIC Theory Exam): Skin Disorders and Diseases Concepts

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Overview

This chapter covers what can go wrong with the skin. You will learn which glands make oil and sweat, how to name a lesion, and which conditions are contagious. A key skill is knowing when a condition is outside your scope and needs a doctor.

Sebaceous glands make oil called sebum, and sudoriferous glands make sweat. When a pore clogs with oil and dead cells, a comedone forms. An open one is a blackhead and a closed one is a whitehead. Acne can then become red bumps and pus-filled spots.

Lesions are grouped as primary or secondary. Primary lesions, such as macules, papules, vesicles, and pustules, appear first on the skin. Secondary lesions, such as crusts, scales, and scars, develop later or from changes in a primary one.

Some conditions spread from person to person. Ringworm (tinea), impetigo, and scabies are contagious, so an esthetician does not treat them and sends the client to a physician. Skin growths and cancers need medical evaluation. Basal cell carcinoma is the most common skin cancer, and melanoma is the most dangerous.

Key concepts

  • Sebaceous glands

    Oil glands attached to hair follicles. They make sebum, which keeps skin soft and helps protect it.

    Memory tipSebaceous = sebum = oil.

  • Sudoriferous glands

    Sweat glands that help cool the body and remove some waste through the skin.

    Memory tipSudoriferous = sweat.

  • Primary lesions

    Changes that appear first on the skin. Examples are macule (flat spot), papule (small raised bump), vesicle (fluid-filled blister), and pustule (pus-filled bump).

    Memory tipPrimary lesions are the first to show.

  • Secondary lesions

    Changes that develop later on the skin. Examples are crust (dried fluid), scale (flakes), and scar (new tissue after injury).

    Memory tipSecondary lesions come after something else.

  • Contagious conditions

    Tinea (ringworm, a fungus), impetigo (bacterial, honey-colored crusts), and scabies (a mite) pass to others easily. Do not provide services; refer the client.

    Memory tipContagious means refer, do not treat.

  • Hyperpigmentation

    Dark patches where the skin makes extra melanin. Melasma and age spots are examples, and sun exposure can make them worse.

    Memory tipHyper means more color; hypo means less.

  • Skin cancers

    Basal cell carcinoma is the most common and rarely spreads. Squamous cell carcinoma is next. Melanoma is the most dangerous because it can spread.

    Memory tipAny changing mole goes to a doctor.

Often tested

  • An esthetician does not diagnose or treat disease.
  • Primary lesions appear first; secondary lesions follow.
  • Refer contagious or unclear conditions to a physician.
  • Melanoma is the most dangerous skin cancer.
  • A blackhead is an open comedone; a whitehead is closed.

Easy to confuse: Primary vs. secondary lesions

TypeExamplesMeaning
PrimaryMacule, papule, vesicle, pustuleFirst changes on the skin
SecondaryCrust, scale, scarDevelop later from other changes

3 sample questions

Verified practice questions from this unit.

Practice questionReviewedScientific Concepts › Skin Disorders and Diseases★★★★★

Question 1. Which glands produce oil (sebum)?

  1. ① Sudoriferous glands
  2. ② Eccrine glands
  3. ③ Sebaceous glands
  4. ④ Pituitary glands
▼ Show answer and explanation▲ Hide answer and explanation

Answer: ③ Sebaceous glands

Key point: Sebaceous glands make oil

Sebaceous (oil) glands are attached to hair follicles. Their oil keeps skin soft, and too much can lead to acne.

Wrong choices

  • Sudoriferous glands: Sudoriferous glands make sweat.
  • Eccrine glands: Eccrine glands are a type of sweat gland.
  • Pituitary glands: The pituitary gland is in the brain.
Practice questionReviewedScientific Concepts › Skin Disorders and Diseases★★★★★

Question 2. What is another name for a blackhead?

  1. ① An open comedone
  2. ② A closed comedone
  3. ③ A milium
  4. ④ A papule
▼ Show answer and explanation▲ Hide answer and explanation

Answer: ① An open comedone

Key point: Blackhead = open comedone

A blackhead is a follicle plugged with oil and cells that is open at the surface. The dark color comes from air changing the plug, not dirt.

Wrong choices

  • A closed comedone: A closed comedone is a whitehead.
  • A milium: A milium is a tiny hard white cyst.
  • A papule: A papule is a small raised bump.
Practice questionReviewedScientific Concepts › Skin Disorders and Diseases★★★★★

Question 3. Which is the most common type of skin cancer?

  1. ① Malignant melanoma
  2. ② Squamous cell carcinoma
  3. ③ Vitiligo
  4. ④ Basal cell carcinoma
▼ Show answer and explanation▲ Hide answer and explanation

Answer: ④ Basal cell carcinoma

Key point: Basal cell = most common skin cancer

Basal cell carcinoma is the most common skin cancer. It often looks like a shiny, pearly bump and grows slowly.

Wrong choices

  • Malignant melanoma: Malignant melanoma is the most serious, not the most common.
  • Squamous cell carcinoma: Squamous cell carcinoma is less common than basal cell.
  • Vitiligo: Vitiligo is a loss of pigment, not a cancer.
Practice 5 questions from this unit →