1 / 78

THE INTEGUMENTARY SYSTEM

Learn about the structure and functions of the integumentary system, including the layers of the skin, cell types, hair structure, and skin appendages. Discover the importance of this system in protecting and regulating the body.

blainee
Download Presentation

THE INTEGUMENTARY SYSTEM

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. THE INTEGUMENTARY SYSTEM

  2. I. Introduction • Basics • Consists of skin, hair, nails, and cutaneous glands. • Largest organ of body • 15-20 sq. ft • 9 lbs • 0.5-4.00 mm thick

  3. B. Layers • Epidermis • Epithelial t. • Dermis • Connective t. • Hypodermis (subcutaneous t.) • Loose connective t. (fat) • Not part of the skin • Anchors the skin to bone and muscle tissue

  4. C. Functions • protection • Vitamin D production • Sensation • Thermoregulation • Excretion (small amount)

  5. II. Epidermis • General • Keratinized, stratified, squamous epithelium • New epidermis every 35-45 days

  6. II. Epidermis • General • Callus – gross thickening due to friction • Blister – acute trauma leads to separation of dermis and epidermis

  7. Epidermis B. Cell types

  8. II. Epidermis B. Cell types • Keratinocytes • Produce fibrous protein keratin • tough, water repellant protein • protects the skin and the underlying tissues from heat, microbes, abrasion and chemicals • Produced in deepest layer

  9. Epidermis B. Cell types

  10. B. Cell types 2. Melanocytes • Produce pigment melanin • Pigment is phagocytized by keratinocytes • Pigment granules protect keratinocytes from UV radiation

  11. B. Cell types 3. Merkel’s cells • Associated w/nerve cell endings – touch reception • Scattered among Kerantinocytes 4. Langerhans’ cells • Macrophage-like • Defend against microorganisms

  12. Epidermis • C. Layers

  13. Hint to remember the layers: Can Little Girls Speak German • Can Corneum • Little Lucidum • GiRls GRanulosum • SPeak SPinosum • GERMan GERMinativum

  14. II. Epidermis C. Layers • Stratum Basalis • Also known as Stratum Germinativum • Single layer • Mitotic

  15. Receive nutrients by diffusion from dermis • Composed of columnar keratinocytes • melanocytes • Merkel’s cells C. Layers • Stratum Basalis

  16. C. Layers • Called the “Spiny Layer” • Less mitotic • Cells are many sided keratinocytes • often called “Prickle Cells” 2.Stratum Spinosum

  17. C. Layers 2.Stratum Spinosum • Scattered among keratinocytes are Langerhans’ cells

  18. Note: The Stratum Basalis and Stratum Spinosum • contain the only epidermal cells that receive adequate nourishment • As the daughter cells are pushed upward, away from the source of nutrition, they gradually die and their soft protoplasm becomes keratinized (hard).

  19. C. Layers • Stratum Granulosum • Granular layer • Keratinization begins • Cells die • Thin layer 2-3 cell layers

  20. C. Layers 4. Stratum Lucidum • Clear layer • Found in thick skin only as palms and soles of feet • Contain Keratin fibrils • Cells begin to degenerate

  21. C. Layers 5. Stratum Corneum • Horny Layer • 20-30 cell layers • ¾ of thickness

  22. C. Layers • Stratum Corneum • Consists of dead flat keratinized cells being sloughed off

  23. II. Epidermis

  24. III. Dermis

  25. III. Dermis • General • Strong, flexible, connective tissue • Thickness: 0.6 – 3 mm

  26. III. Dermis • General • Has collagenous & reticular fibers

  27. A. General 4. Contains • Blood vessels • Nerves • Hair follicles • Sebaceous glands • Sweat glands • Nail roots

  28. A. General 5. Epidermis projects into dermis to form • Sebaceous glands • Sweat glands • Hair follicles

  29. III. Dermis B. Layers

  30. B. Layers • Papillary Layer • Closest to epiderms • Made of areolar, loose con. t. • Has Dermal Papillae • Finger-like projects that indent into the epidermis

  31. c. Has Dermal Papillae • Contain • Capillaries • pain receptors • Meisner corpuscles: light touch receptors • Finger prints

  32. III. Dermis B. Layers 2.Reticular layer • Deepest layer • Comprises 4/5 of dermis • Made of dense irregular connective tissue

  33. III. Dermis B. Layers 2.Reticular layer • Rich in blood vessels and nerve • Pacinian corpuscles – sense deep pressure, heat and cold

  34. III. Dermis B. Layers 2.Reticular layer • f. Tension lines or cleavage – separation of collagen bundles • g. Flexure line – folding of dermis at joints of wrists, palms, fingers toes

  35. IV. Hypodermis • Areolar and adipose tissue • Anchors skin to organs • Insulates, absorbs shock, stores fat

  36. V. Skin Appendages • General • Organs that develop from the embryonic epidermis • Also called epidermal derivatives

  37. V. Skin Appendages • General • Includes • Hair • Sweat glands • Sebaceous glands • Finger nails • Tooth enamel

  38. V. Skin Appendages B. Hair • Is fused keratinized cells • Protects against • Scalp injury • Sun • Heat loss

  39. B. Hair 3. Structure • Shaft • Above surface • Shape determines curliness • Round = straight • Oval = wavy • Flat = kinky

  40. 3. Structure a. Shaft • Root • Extends from epidermis to dermis • Extends into hypodermis in scalp

  41. Note: The root and shaft are made of 3 tubes

  42. Note: 3 tubes • cuticle: outer tube 1 layer of heavily keratinized cells. • cortex: middle tube several layers of cells w/ pigments in dark hair and air bubbles in white hair. • medulla: inner tube made of 2 -3 rows of cells with pigments and air spaces.

  43. B. Hair 4. Follicle • Provides nutrients • Matrix produces hair • Arrector pili muscle – goose bumps

  44. V. Skin Appendages • Hair 4. Split ends – cuticle wears away • Color results from melanin (black, brown, yellow) • Hair growth – nutrition, hormones

  45. V. Skin Appendages • Hair • Kinds of hair • Vellus hair: fine pale body hair of women and children • Terminal hair: coarse, scalp, pubic region, male body hair P141 hirsutism

More Related