Ch. 4 Integumentary System : The Skin and Its Parts

1. Ch. 4 Integumentary System: The Skin and Its Parts

2. Applied Learning Outcomes 1. Use terminology associated with the Integumentary system 2. Learn about skin structure, function, appendages, glands, and care 3. Understand the aging and pathology of the Integumentary system

3. Case Study Investigation – Ch. 4 You are observing an elderly woman who is seeing a personal trainer as part of her rehabilitation therapy. The woman was hospitalized for problems associated with obesity & high blood sugar. She is now going through an exercise program to helpb bring her back to health. While working out, one of her socks rolled down exposing the lower part of her leg. A glance at the side of her left leg, revealed a large, shiny, deep red

4. sore. The sore had a dark margin, like tanned skin. Parts of it looked as if you could see right through to the muscle. The woman saw your face reacting to the sore and kindly said, “Don’t worry about that, it doesn’t cause me any pain.” Part of the personal’s trainer’s responsibility is to pay attention to the pathology that can be worsened by the patient’s rehab. By the end of this chapter you will be asked to determine the possible problems causing this skin condition.

5. Human Skin Trivia • skin – largest organ in body (25sq.ft or 16% of your body weight) • lose an avg. of _____________ hairs/day • _____________________________ • avg. scalp has ______________ hairs • shed _______ of skin/lifetime on avg. (1 layer every 24 hrs) • body loses 30,000–40,000__________/min • __________________of nerves in skin • blondes have more hair than brunettes

6. Did You Know? _________________ is the fear of hair. __________________is the fear of haircuts.

7. Did You Know? Hair generally grows at a rate of approximately _____per day, or approximately _____per month.

8. Did You Know? Hair is naturally colored by pigment granules ____________in the cortex whereas dyed hair has melanin in the ____________ as well as the cortex.

9. Overview The skin is the largest organ is in the body and is composed of: _________________ Nerve Hair __________ Skin ______________ Receptors

10. Overview ___________: qualities an organism is ____ with ex. Genes for making ________ only turn on in the upper tips of the fingers and toes ___________: ability of an organism’s genes to respond to ____________________ changes ex. calluses, _________, skin stretches as the body grows and shrinks back after a woman gives birth

11. Functions of Integumentary System • _____________ - against environment (UV rays, microbes); and self-repairs cuts & burns • _____ regulation – maintain homeostasis (blood vessels) • ___________________– prevents water from flushing out important nutrients • Sensation– ________________________ from the environment (receptors) • __________________ - can receive O2, N2, medicine • __________ excretion – can excrete CO2, urea, sweat • Synthesis of Vitamin D – Vit. D helps maintain normal blood __________________ & phosphorus

12. 3 Major Layers of the Skin • _________________ • a. __________________tissue (epithelial) • b. strong & waterproof (keratin) • _______________ • a. dense connective tissue • b. contains blood, sweat • & oil glands • 3. Hypodermis (subcutaneous) • a. __________________ • anchors skin (E & D) • to underlying organs

13. Epidermis - get a new one every 25-45 days - melanocytes (melanin cells) - keratocytes (keratin cells) Dermis - functional layer Hypodermis / Subcutaneous - adipose tissue Microscopic View

14. 5 Layers of the Epidermis • 1. Stratum ___________ • (_______ cells & melanin • which gives skin color) • 2-4. middle layers • (protein __________ • provides strength) • stratum • ___________________ • (______________ & dividing cells) OUTSIDE THE BODY***** DERMIS*****

15. Why don’t we bleed when we shave?? • The epidermis is ________________, meaning it has no blood supply of its own. • You only bleed if you cut deep enough to reach the _______________.

16. Dermis • __________________ layer • contains ______________, sweat & oil glands, hair follicles, __________ fibers, _____________endings & elastic fibers • __________________ finger-like projections of the dermis that • __________ epidermis & dermis • form ridges & grooves that create _________________

17. Dermal papillae

18. Hypodermis (subcutaneous) • composed of ___________ tissue & elastic fibers • ___________skin to underlying fascia(tissue that covers muscles, skull & some organs) • major blood vessels & nerves branch upward into the dermis • absent/thin in eyelids, penis, scrotum, & nipples; responsible for increase in breasts & hips in females

19. Subcutaneous Injection • ideal site for rapid & relatively pain free absorption of injected material (i.e. insulin/ flu shot) using a _______________ needle

20. Concept Check Questions 1-3 1. List 5 major components of the Integumentary system? 2. Distinguish between inherent and adaptive characteristics. Give an example of each. 3. List 5 main functions of the Integumentary system?

21. Concept Check Questions 4-6 4. What are the 3 layers of skin from superficial to deep? 5. What kind of tissues can be found within each layer of skin? 6. How do the 5 layers of the epidermis differ? Be specific.

22. Concept Check Questions 7-9 7. Why don’t we bleed when we shave usually? When would you see blood? 8. Why is the dermis considered the “functional” layer? 9. Where are dermal papillae found AND what 2 functions are they responsible for?

23. Skin Appendages • assist skin with its functions • glands • nerves • nails • hair

24. Blood Vessels • ______________________ according to internal body temperature of body 1. warm body blood flow ________ heat leaves 2. cold body blood flow _________ heat stays 3. _____ evaporation  lowers body temperature

25. Glands • 3 types of glands commonly found in skin • ___________________ glands (wax) • _____________________glands (oil) 3. sweat a. _________________________glands b. ________________________glands

26. Ceruminous Glands • produce ___________ or ear wax that line ear canal • surrounded by small hairs • collects ____ & dust and _____________ of the ear

27. Sebaceous Glands • attached to _______________________ • produces _____________, an oily secretion • sebum _______________ hair and surface of skin to prevent them from drying out

28. Sweat Glands • produces sweat through_____ • 2 types a) Apocrine: • responsible for ___________ • found in groin, naval, armpits & areolae

29. Apocrine Sweat Glands • _____________________& taper off in activity in elders • secretions contain _________________ (play a role in courtship & social behavior) • dogs are notorious for sniffing these secretions • secretions are readily broken down by ______________  creates body odors

30. b) Eccrine: • found ____________; concentrated in armpits, forehead, palms & soles of feet • composed of salt & ________  activity, amount & distribution is __________________ determined

31. Eccrine Sweat Glands • allow chemicals causing food odors leak out of the body • bacteria feed off nutrients in sweat  causing odors • _______________________ reduce amont of sweat produced by glands  reduce dampness & odors • (-) charged ingredients repel (-) charged sweat molecules

32. Nerves Sensory receptors: • ________________ information from the environment to the body • found in all skin layers; concentrated in dermis & fascia

33. Types of Sensory Receptors __________endings: • detect __________ • in the epidermis

34. Types of Sensory Receptors _________________corpuscles: • in dermis • detect ________ dermal papillae --------------- Also  Krause end bulbs (cold temp.)

35. Types of Sensory Receptors ________ corpuscles: • deep in dermis & hypodermis • detect strong _______________ (vibrations) -------------------- also  Ruffini receptors

37. Nails • nail root lies beneath cuticle (skin fold) • __________ in nail root move up, die & flatten  forms nail body • lunula- moon shaped whitish area • nails grow 1/8 in/mo. faster than toenails

38. Hair • each strand of hair grows from a hair follicle (inward protrussion of epidermis) • ________________(base of follicle) has its ______ blood & nerve supply • hair shaft - ________ hardened, keratinized stratum corneum-like cells

39. Layers of Hair • 3 layers  cuticle, cortex & medulla • ___________ thin, colorless, _________ cortex & scales point toward tip; large in humans • ________  strength, ______ & texture • _________ only present in thick hair; small or non-exsitent in humans

40. Medulla – central core(may be absent) Cortex – protein-rich structure around the medulla that contains ____________ Hair Structure Cuticle – outer coating composed of overlapping ______________ The structure of hair has been compared to that of a pencil with the medulla being the ________, the cortex being the _________ and the cuticle being the __________ on the outside.

41. http://www.videojug.com/interview/csi-and-trace-evidence-2

42. Hair • color determined by ________________ • amount & location determines color  genetically controlled • _____________muscle (smooth muscle) attachs to hair follicle  causes goosebumps (__________)

43. Drugs & Hair • capture many ____________ (drug/poison) that pass through blood • advantages: 1) goes back months not days 2) non-invasive, 3) holds up in court • disadvantages: 1) expensive, 2) takes time to get results

44. Stages of Hair Development: Root must be present in order to test hair evidence for DNA Anagen: ____________ Catagen: ___________ Telogen: ____________

45. Habits & Hair Loss • hair loss is a slowing down of hair growth and replacement • physical _______is a major cause of hair loss (childbirth, illness, injury, pregnancy, and too much exercise • when body has to use its energy to cope with stress to places hair growth as a lower priority • __________________________________(diets low in amino acids) • increase in _______________________ • tight braids or ponytails might also pull off hair faster than it can be replaced • excessive ________________________ • _______________________seems to accelerate growth

46. Concept Check Questions 10-12 10. What are skin appendages? Provide 4 examples. 11. The dermis has the ability to regulate heat. Describe 3 ways the dermis does this. 12. What do ceruminous & sebaceous glands produce and how do these secretions differ in function?

47. Concept Check Questions 13-15 13. Describe how appocrine & eccrine glands differ in location and what they secrete. 14. What is the general function of nerves/receptors in the skin? Name 3 & state what each detects. 15. Describe the differences btwn the 3 layers of hair.

48. Concept Check Questions 16-18 16. Why doesn’t a hair cut hurt, but pulling a hair out of the head does? 17. What does the arrector pili muscle attach to and what’s its function? 18. What are the advantages & disadvantages of the testing hair samples for drugs?

49. Burns • causes skin to lose ability to maintain homeostasis • majority of burns ____ exposure & cooking accidents • other causes ___________, electricity, ______ & steam

50. Types of Burns • 1st Degree  ______________ damage; reddening and swelling • chemicals, steam, flame heat & mild sun exposure http://videos.howstuffworks.com/howstuffworks/131-how-sunburns-work-video.htm