chapter 5 the integumentary system

Question 1

What are the three layers of skin?

Answer 1

Epidermis (outer shield), Dermis (middle cushion), Hypodermis (deep fatty layer).

Question 2

What are the traits of the epidermis?

Answer 2

Protective, avascular (no blood flow), made of keratinized stratified squamous epithelium.

Question 3

What are the main types of cells in the epidermis?

Answer 3

Keratinocytes (keratin factory), Melanocytes (melanin for skin color), Langerhans’ cells (immune warriors), Merkel cells (touch detectors).

Question 4

What is the Stratum Corneum?

Answer 4

Top layer of the epidermis, consisting of 20-30 dead, flat cells that shield and waterproof.

Question 5

What is the Stratum Lucidum?

Answer 5

Only found in thick skin (palms, soles), composed of clear, dead keratinocytes.

Question 6

What occurs in the Stratum Granulosum?

Answer 6

Keratinization starts here; granules act as water-loss blockers.

Question 7

What is the Stratum Spinosum?

Answer 7

Thick layer with web-like pre-keratin filaments and Langerhans’ cells.

Question 8

What is the Stratum Basale?

Answer 8

Deepest layer of the epidermis, serves as stem cell headquarters; contains melanocytes and Merkel cells.

Question 9

What are the two layers of the dermis?

Answer 9

Papillary (light touch and pain/temp) and Reticular (tough collagen and stretchy elastin).

Question 10

What is the function of the hypodermis?

Answer 10

Acts as a fat cushion for shock absorption and insulation.

Question 11

What are the main skin pigments?

Answer 11

Melanin (yellow to black), Carotene (orange), Hemoglobin (pink/red from blood flow).

Question 12

What are the types of sweat glands?

Answer 12

Eccrine (watery sweat for cooling) and Apocrine (stinky sweat, starts at puberty).

Question 13

What are specialized sweat glands?

Answer 13

Ceruminous (earwax) and Mammary (milk).

Question 14

What do sebaceous glands produce?

Answer 14

Sebum (oil) for lubrication and bacteria-killing; absent on palms and soles.

Question 15

What is hair made of?

Answer 15

Dead keratin; melanin determines color.

Question 16

What are the types of hair?

Answer 16

Vellus (soft baby hair) and Terminal (thick hair on scalp, brows, pubes).

Question 17

What are nails made of?

Answer 17

Hard keratin plates for protection.

Question 18

What are the functions of the skin?

Answer 18

Protection (physical, chemical, immune), Temperature regulation (sweat + blood vessel dilation), Sensation (touch/pain detection).

Question 19

What role does the skin play in Vitamin D production?

Answer 19

Skin acts as a sunlight lab for making this vital vitamin.

Question 20

What are the types of skin cancer?

Answer 20

Basal cell carcinoma (common, least dangerous), Squamous cell carcinoma (middle-ground danger), Melanoma (rare, deadly).

Question 21

What are the ABCDEs of melanoma?

Answer 21

Asymmetry, Border irregularity, Color variation, Diameter > 6mm, Elevation.

Question 22

What are the degrees of burns?

Answer 22

1st degree (red, hurts - epidermis only), 2nd degree (blisters - epidermis + upper dermis), 3rd degree (full thickness, no pain).

Question 23

What is the Rule of Nines?

Answer 23

Quick burn severity estimate; critical if 25% of body = 2nd degree, 10% = 3rd degree, or face/hands/feet = 3rd degree.

Question 24

What changes occur in aging skin?

Answer 24

Skin becomes thin, dry, wrinkly, less elastic; higher cancer risk due to fewer melanocytes and immune cells.