CMP Anatomy of Skin & Hair 3 — Questions and Answers
Question 1: Which cells in the epidermis produce melanin and transfer it to surrounding keratinocytes?
- Merkel cells
- Langerhans cells
- Melanocytes (Correct answer)
- Fibroblasts
Correct answer: Melanocytes
Melanocytes in the stratum basale synthesize melanin and transfer it via melanosomes to neighboring keratinocytes for UV protection.
Question 2: The sebaceous gland secretes sebum via which mechanism?
- Merocrine secretion
- Apocrine secretion
- Holocrine secretion (Correct answer)
- Eccrine secretion
Correct answer: Holocrine secretion
Sebaceous glands use holocrine secretion, in which entire cells disintegrate to release their lipid-rich sebum contents.
Question 3: What is the approximate pH of the skin's acid mantle, which protects against pathogens?
- 3.0–3.5
- 4.5–5.5 (Correct answer)
- 6.5–7.0
- 7.5–8.0
Correct answer: 4.5–5.5
The skin's acid mantle maintains a pH of approximately 4.5–5.5, inhibiting bacterial and fungal growth on the skin surface.
Question 4: Which layer of the dermis contains most of the collagen bundles, elastic fibers, blood vessels, and hair follicles?
- Papillary dermis
- Reticular dermis (Correct answer)
- Hypodermis
- Stratum basale
Correct answer: Reticular dermis
The reticular dermis is the deeper, thicker dermal layer composed of dense irregular connective tissue with coarse collagen bundles.
Question 5: In the nail anatomy, what name is given to the crescent-shaped white area at the base of the nail plate?
- Hyponychium
- Eponychium
- Lunula (Correct answer)
- Nail bed
Correct answer: Lunula
The lunula is the visible white crescent at the proximal nail plate where nucleated cells from the nail matrix are still present.
Question 6: Which fiber type in the dermis provides elasticity and allows skin to snap back after stretching?
- Collagen type I
- Collagen type III
- Elastic fibers (Correct answer)
- Reticular fibers
Correct answer: Elastic fibers
Elastic fibers composed of elastin allow the skin to return to its original shape after mechanical deformation.
Question 7: The telogen phase of hair growth typically lasts how long before the hair is shed?
- 1–2 weeks
- 2–3 weeks
- 2–3 months (Correct answer)
- 6–12 months
Correct answer: 2–3 months
The telogen (resting) phase lasts approximately 2–3 months, after which the old hair is shed and a new anagen cycle begins.
CMP Anatomy of Skin & Hair 3
Which cells in the epidermis produce melanin and transfer it to surrounding keratinocytes?