CHAPTER 6 TEST REVIEW Flashcards
what are the 3 layers of the skin
The three layers of skin are epidermis the dermis and the subcutaneous layer. The sublayer is considered not technically a part of the system.
what are the 5 layers of the epidermis (deep/superficial)
The five layers from deep to superficial
1. Stratum basale
2. Stratum spinosum
3. Stratum granulosum
4. Stratum lucidum
5. Stratum corneum
* First three layers composed of living keratinocytes
what are 3 cells types of the stratum basale
- Keratinocytes
- Melanocytes
- Tactile cells
what is the pigment secreted by the melanocytes
melanin
what is Merkel cell
Tactile cells
* Merkel cells
* Few in number
* Sensitive to touch
* When compressed, release chemicals, stimulate sensory nerve
endings
what are Langerhans cells
Epidermal dendritic cells (Langerhans cells) found in
stratum spinosum and granulosum
* Initiate immune response
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what is eleidin
Cells filled with a translucent protein, eleidin
Stratum lucidum
* Translucent layer, 2 to 3 cell layers thick
* Found only on thick skin on palms and soles
thick vs thin skin (what is the difference the between thick skin and thin skin)
Thick skin
* Palms of hands, soles of feet
* Contains all five layers of epidermal strata
* Sweat glands but no hair follicles or sebaceous glands
* Thin skin
* Covers most of body
* Lacks a stratum lucidum
* Sweat glands, hair follicles, and sebaceous glands
what are examples of skin markings
Skin markings:
Nevus (mole)
* Localized overgrowth of melanocytes
* Should be monitored for changes suggesting malignancy
Freckles
* Yellowish or brown spots
* Localized areas of increased melanocyte activity
Hemangiomas
* Skin discoloration due to benign blood vessel tumor
Friction ridges
* Large folds and valleys of dermis and epidermis
* Fingerprints
what is described in the View: UV Radiation, Sunscreens, and Sunless
Tanners
Sun generates UVA, UVB, UVC radiation
* UVC rays absorbed and do not reach earth
Sunscreens block UVA and UVB rays
* Protect skin if used correctly
* Need high enough SPF (sun protection factor)
Sunless tanners create tanned skin without UV light
exposure.
* No protection against UV rays
what are the 2 layers of the dermis
Papillary and reticular layers
what is described in the Clinical View: Tattoos
- Permanent images produced on integument
- Dye injected into dermis
- Permanent part of dermis layer
- Usually impossible to completely remove a tattoo
- Lasers used to break down pigments
- Newer inks are available that allow for removal
what are the functions of the skin
Protection from the external environment
Prevention of water loss/gain
Vitamin D synthesis
Secretion
Absorption
Immune function
Temperature regulation
Sensory reception
what are the structures of the nails
Structure of nails
* Scalelike modifications of stratum corneum
* Dorsal edges of fingers and toes
* Protect distal tips of digits
* Assist in grasping objects
* Distal whitish free edge (no underlying capillaries)
* Pinkish nail body (underlying capillaries)
* Nail root (part embedded in skin)
* These three constitute nail plate
* Nail bed
* Layer of living epidermis covered by nail body
what are the types of hair
Lanugo: fine, unpigmented, downy hair
* Appears in last trimester
* Vellus: fine hair
* Primary human hair
* Found on upper and lower limbs
* Terminal hair: coarser, pigmented, longer
* On scalp, eyebrows, and eyelashes, men’s beards
* During puberty, replaces vellus hair in axillary and pubic regions