2. Organization – Skin Epidermis Dermis – Accessory Structures Hair & Hair follicles Exocrine glands Arrector pili Sensory Receptors

3. Layers beneath the skin – Subcutaneous layer – Deep fascia ________________________

5. Functions of the Skin – Protection – Water-resistance – Temperature regulation – Vitamin D synthesis – Sensations – Immunity – Social signaling

6. –Stratum Germinativum Stem cells Melanocytes Merkel cells  The Epidermis

8. – S. Spinosum “Pre- keratinocytes” Melanocytes Langerhans cells  The Epidermis

10. – S. Granulosum – S. Lucida Keratinocytes in both layers  The Epidermis

11. – S. Corneum Dead keratinocytes  The Epidermis

12. Skin cell-eating mite

13.  The Dermis

14. Reticular layer – Dense irregular CT – Provides strength and elasticity

15.  The Dermis Papillary layer – Areolar CT – Contains cap’s and sensory neurons for epidermis – Arranged as dermal papillae –

17.  Pigmentation Melanin Carotene Hemoglobin

18.  Epidermal Derivatives Hair Follicles and Hair Skin Glands

19.  Hair Function – Protection – Touch Sensation Structure – Root – Shaft – Bulb

20.  Hair Hair Follicle – Sheath of epithelial cells – Surrounds root – Merges with bulb

22.  Hair Associated structures – Dermal papilla – Sebaceous glands – Arrector pili

23.  Hair Growth Cycle – 2-5 yrs: growth stage – 2 yrs: resting stage

24.  Skin Glands Sebaceous glands – secrete sebum – help to protect hair and skin

25.  Skin Glands Merocrine (eccrine) sweat glands – BT control – excretion – protection

26.  Skin Glands Apocrine sweat glands – Secrete pheromones?

27.  Skin Glands Mammary glands Ceruminous glands

28.  Skin Sensory Receptors Free nerve endings Pacinian corpuscles Meissner’s corpuslces

29. Lines of Cleavage