Regulated by the Texas Department of Licensing and Regulation (TDLR)
Q1. What is the largest organ of the human body?
ANSWER The skin
Q2. What are the three main layers of the skin?
ANSWER Epidermis, dermis, and hypodermis (subcutaneous layer)
Q3. What is the outermost layer of the skin called?
ANSWER The epidermis
Q4. Which layer of the epidermis contains melanocytes?
ANSWER The stratum basale (basal layer)
Q5. What are the five layers of the epidermis from deepest to outermost?
ANSWER Stratum basale, stratum spinosum, stratum granulosum, stratum lucidum,
stratum corneum
Q6. What is the stratum corneum?
ANSWER The outermost layer of the epidermis, composed of dead keratinized cells
Q7. What is keratin?
ANSWER A fibrous protein that makes up the outer layer of skin, hair, and nails
Q8. What cells produce melanin?
ANSWER Melanocytes
Q9. What is melanin?
ANSWER The pigment that gives skin, hair, and eyes their color and protects
against UV radiation
Q10. What is the dermis?
ANSWER The middle layer of skin containing collagen, elastin, blood vessels,
nerves, hair follicles, and sweat glands
Q11. What proteins give skin its strength and elasticity?
, ANSWER Collagen and elastin
Q12. What is the function of sebaceous glands?
ANSWER They produce sebum (oil) to lubricate and protect the skin and hair
Q13. What are the two types of sweat glands?
ANSWER Eccrine glands (regulate body temperature) and apocrine glands (located
in armpits and groin)
Q14. What is the hypodermis?
ANSWER The deepest layer of skin, composed of fat and connective tissue that
insulates and cushions the body
Q15. What is the average pH of healthy skin?
ANSWER 4.5 to 5.5 (slightly acidic)
Q16. What is the acid mantle?
ANSWER The thin protective film on the skin's surface formed by sebum and sweat
that maintains slightly acidic pH
Q17. What is desquamation?
ANSWER The natural shedding of dead skin cells from the stratum corneum
Q18. How long does skin cell turnover typically take in a young adult?
ANSWER Approximately 28 days
Q19. What is a Langerhans cell?
ANSWER An immune cell in the epidermis that helps protect against pathogens and
allergens
Q20. What is the stratum lucidum?
ANSWER A thin, translucent layer of the epidermis found only on the palms and
soles
Q21. What is transepidermal water loss (TEWL)?
ANSWER The process by which water evaporates through the skin surface
Q22. What is the function of the natural moisturizing factor (NMF)?
ANSWER To maintain skin hydration by attracting and retaining water in the
stratum corneum
Q23. What are fibroblasts?
ANSWER Cells in the dermis that produce collagen and elastin
Q24. What is the Fitzpatrick skin type scale?
, ANSWER A classification system that categorizes skin types I through VI based on
response to UV exposure
Q25. What is Fitzpatrick skin type I?
ANSWER Very fair skin that always burns, never tans
Q26. What is Fitzpatrick skin type VI?
ANSWER Very dark skin that never burns and always tans deeply
Q27. What is sebum?
ANSWER The oily secretion produced by sebaceous glands that lubricates skin and
hair
Q28. What is a comedone?
ANSWER A plugged hair follicle filled with sebum and dead cells; can be open
(blackhead) or closed (whitehead)
Q29. What causes an open comedone (blackhead) to appear dark?
ANSWER Oxidation of melanin and sebum when exposed to air, not dirt
Q30. What is a pustule?
ANSWER A small inflamed lesion filled with pus
Q31. What is a papule?
ANSWER A small, solid, raised lesion without pus
Q32. What is a macule?
ANSWER A flat, discolored spot on the skin, such as a freckle or age spot
Q33. What is a vesicle?
ANSWER A small blister filled with clear fluid
Q34. What is a wheal?
ANSWER A raised, itchy area of skin, such as from a hive or insect bite
Q35. What is a nodule?
ANSWER A large, solid, raised lesion deeper than a papule
Q36. What is a cyst?
ANSWER A closed sac filled with fluid or semi-solid material beneath the skin
Q37. What is telangiectasia?
ANSWER Dilated capillaries visible on the skin surface, also called spider veins or
couperose
Q1. What is the largest organ of the human body?
ANSWER The skin
Q2. What are the three main layers of the skin?
ANSWER Epidermis, dermis, and hypodermis (subcutaneous layer)
Q3. What is the outermost layer of the skin called?
ANSWER The epidermis
Q4. Which layer of the epidermis contains melanocytes?
ANSWER The stratum basale (basal layer)
Q5. What are the five layers of the epidermis from deepest to outermost?
ANSWER Stratum basale, stratum spinosum, stratum granulosum, stratum lucidum,
stratum corneum
Q6. What is the stratum corneum?
ANSWER The outermost layer of the epidermis, composed of dead keratinized cells
Q7. What is keratin?
ANSWER A fibrous protein that makes up the outer layer of skin, hair, and nails
Q8. What cells produce melanin?
ANSWER Melanocytes
Q9. What is melanin?
ANSWER The pigment that gives skin, hair, and eyes their color and protects
against UV radiation
Q10. What is the dermis?
ANSWER The middle layer of skin containing collagen, elastin, blood vessels,
nerves, hair follicles, and sweat glands
Q11. What proteins give skin its strength and elasticity?
, ANSWER Collagen and elastin
Q12. What is the function of sebaceous glands?
ANSWER They produce sebum (oil) to lubricate and protect the skin and hair
Q13. What are the two types of sweat glands?
ANSWER Eccrine glands (regulate body temperature) and apocrine glands (located
in armpits and groin)
Q14. What is the hypodermis?
ANSWER The deepest layer of skin, composed of fat and connective tissue that
insulates and cushions the body
Q15. What is the average pH of healthy skin?
ANSWER 4.5 to 5.5 (slightly acidic)
Q16. What is the acid mantle?
ANSWER The thin protective film on the skin's surface formed by sebum and sweat
that maintains slightly acidic pH
Q17. What is desquamation?
ANSWER The natural shedding of dead skin cells from the stratum corneum
Q18. How long does skin cell turnover typically take in a young adult?
ANSWER Approximately 28 days
Q19. What is a Langerhans cell?
ANSWER An immune cell in the epidermis that helps protect against pathogens and
allergens
Q20. What is the stratum lucidum?
ANSWER A thin, translucent layer of the epidermis found only on the palms and
soles
Q21. What is transepidermal water loss (TEWL)?
ANSWER The process by which water evaporates through the skin surface
Q22. What is the function of the natural moisturizing factor (NMF)?
ANSWER To maintain skin hydration by attracting and retaining water in the
stratum corneum
Q23. What are fibroblasts?
ANSWER Cells in the dermis that produce collagen and elastin
Q24. What is the Fitzpatrick skin type scale?
, ANSWER A classification system that categorizes skin types I through VI based on
response to UV exposure
Q25. What is Fitzpatrick skin type I?
ANSWER Very fair skin that always burns, never tans
Q26. What is Fitzpatrick skin type VI?
ANSWER Very dark skin that never burns and always tans deeply
Q27. What is sebum?
ANSWER The oily secretion produced by sebaceous glands that lubricates skin and
hair
Q28. What is a comedone?
ANSWER A plugged hair follicle filled with sebum and dead cells; can be open
(blackhead) or closed (whitehead)
Q29. What causes an open comedone (blackhead) to appear dark?
ANSWER Oxidation of melanin and sebum when exposed to air, not dirt
Q30. What is a pustule?
ANSWER A small inflamed lesion filled with pus
Q31. What is a papule?
ANSWER A small, solid, raised lesion without pus
Q32. What is a macule?
ANSWER A flat, discolored spot on the skin, such as a freckle or age spot
Q33. What is a vesicle?
ANSWER A small blister filled with clear fluid
Q34. What is a wheal?
ANSWER A raised, itchy area of skin, such as from a hive or insect bite
Q35. What is a nodule?
ANSWER A large, solid, raised lesion deeper than a papule
Q36. What is a cyst?
ANSWER A closed sac filled with fluid or semi-solid material beneath the skin
Q37. What is telangiectasia?
ANSWER Dilated capillaries visible on the skin surface, also called spider veins or
couperose
