Memmler’s Structure and Function of the Human Body, 10th Edition
Jason James Taylor and Barbara Janson Cohen
Answers to “Questions for Study and Review”
Chapter 5. The Integumentary System
Building Understanding
Fill in the Blank
1. integumentary
2. keratin
3. apocrine
4. arrector pili
5. melanin
Matching
6. (d) stratum corneum
7. (b) stratum basale
8. (a) pressure receptor
9. (c) ceruminous gland
10. (e) meibomian gland
Multiple Choice
11. (a) superficial
12. (b) dermis
13. (d) dermal papillae
14. (b) sudoriferous
15. (d) nail root
Understanding Concepts
16. Epidermis, the outermost portion of skin, is composed entirely of epithelium and contains no blood vessels. Deep to epidermis is the dermis, composed of connective tissue with many blood vessels, nerve endings, and glands. Deep to the dermis is the hypodermis, or subcutaneous tissue, which is not considered part of skin. It is composed of connective tissue and anchors the skin to the surface muscles. New epidermal cells produced in the stratum basale replace the outermost cells of the epidermis.
17. Sebaceous (oil) glands are located in the dermis near hair follicles, where they release sebum that lubricates the hair and skin. Sudoriferous glands are located in the dermis and hypodermis and release sweat on the surface of the skin, helping to cool the body.
18. The four most important functions of skin are protection against infection, protection against dehydration, temperature regulation, and sensation.
19. Skin wound healing begins with blood bringing growth factors that stimulate restorative cells and agents that break down tissue debris and fight infection. New vessels branch into the injured tissue. Fibroblasts make collagen to close the wound. A large injury requires growth of new connective tissue, which sometimes leads to scar formation. Formation of a scab, or crust, over the wound may protect injured tissue, but slows healing and promotes scarring.
20. As skin ages the dermis thins and collagen becomes less abundant, which results in wrinkles, transparency, and a loss of elasticity. Localized areas may become more pigmented (liver spots), while most of the skin becomes paler because of a decrease in circulation to the dermis.
Conceptual Thinking
21. ● The skin is an organ because it is composed of more than one primary tissue type.
22. ● In Paul’s case, chronic sun overexposure damaged the epidermal layer called the stratum basale.
● The stratum basale is the epidermal layer most likely to become cancerous because it is composed of actively dividing cells.