CHAPTER 6 TEST REVIEW

Question 1

what are the 3 layers of the skin

Answer 1

The three layers of skin are epidermis the dermis and the subcutaneous layer. The sublayer is considered not technically a part of the system.

Question 2

what are the 5 layers of the epidermis (deep/superficial)

Answer 2

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

Question 3

what are 3 cells types of the stratum basale

Answer 3

1. Keratinocytes
2. Melanocytes
3. Tactile cells

Question 4

what is the pigment secreted by the melanocytes

Answer 4

melanin

Question 5

what is Merkel cell

Answer 5

Tactile cells
* Merkel cells
* Few in number
* Sensitive to touch
* When compressed, release chemicals, stimulate sensory nerve
endings

Question 6

what are Langerhans cells

Answer 6

Epidermal dendritic cells (Langerhans cells) found in
stratum spinosum and granulosum
* Initiate immune response
10

Question 7

what is eleidin

Answer 7

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

Question 8

thick vs thin skin (what is the difference the between thick skin and thin skin)

Answer 8

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

Question 9

what are examples of skin markings

Answer 9

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

Question 10

what is described in the View: UV Radiation, Sunscreens, and Sunless
Tanners

Answer 10

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

Question 11

what are the 2 layers of the dermis

Answer 11

Papillary and reticular layers

Question 12

what is described in the Clinical View: Tattoos

Answer 12

• 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

Question 13

what are the functions of the skin

Answer 13

Protection from the external environment

Prevention of water loss/gain

Vitamin D synthesis
Secretion

Absorption

Immune function

Temperature regulation

Sensory reception

Question 14

what are the structures of the nails

Answer 14

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

Question 15

what are the types of hair

Answer 15

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

Question 16

what is arrector pili

Answer 16

one of the hair components
Thin ribbons of smooth muscle
* Extend from hair follicle to dermal papillae
* Elevates hair with contraction, “goosebumps”

Question 17

what are the functions of hair

Answer 17

Protection
* On head, from sunburn and injury
* Respiratory system and ears – hair traps particles, debris
* Heat retention
* Sensory reception
* Root hair plexuses detect light touch
* Visual identification

Question 18

what are the 3 phases of the hair growth cycle

Answer 18

Anagen—active phase of growth
2. Catagen—brief regression period where cell division
stops
3. Telogen—resting phase, period when hair is usually shed

Question 19

what is alopecia areata

Answer 19

Autoimmune disorder where follicles are attacked
* Spots of baldness on scalp and body

Question 20

what is hirsutism

Answer 20

Excessive hairiness

Question 21

what are the 2 types of sweat glands and which are the (most numerous)

Answer 21

Sweat glands include two types
* Merocrine
* Apocrine
Merocrine (eccrine) sweat glands
* Most numerous and widely distributed
* Simple, coiled tubular glands
* Discharge secretions onto skin surface
* Produce secretion by exocytosis
Secrete sweat

Question 22

what is sweat (composition)

Answer 22

Composed of 99% water and 1% other chemicals
* Includes: electrolytes, metabolites, and waste products

Question 23

what is sebum

Answer 23

Produce oily secretion, sebum
* Lubricant for skin and hair
* Bactericidal
* Discharges into a hair follicle

Question 24

what is cerumen

Answer 24

Secretions of waterproof earwax, cerumen
* Traps foreign material
* Lubricates acoustic meatus and eardrum

Question 25

what is described in the Clinical View: Acne and Acne Treatments

Answer 25

Acne * Plugged sebaceous ducts * Typically begins during puberty * Increased activity gland secretions may block pores * Treatments * Benzoyl peroxide, salicylic acid, antibiotics, vitamin A–like compounds, systemic retinoids * May lead to scarring if untreated

Question 26

what are the 2 ways a tissue is repaired

Answer 26

Tissue is repaired in one of two ways: regeneration or fibrosis * Regeneration * Replacement of damaged or dead cells with same cell type * Restores organ function * Fibrosis * Gap filled with scar tissue * Collagen produced by fibroblasts * Functional activities not restored

Question 27

what is described in the Clinical View: Psoriasis

Answer 27

Chronic autoimmune skin disease Keratinocytes attacked by T-lymphocytes Causes rapid overgrowth of new skin cells Patches of whitish, scaly skin on epidermal surface Symptoms: severe itching, pain, skin cracking Treatments * Corticosteroids, UV light therapy, medications that interfere with skin cell production

Question 28

what are the degree of burns (appearance)

Answer 28

First degree burns * Involve only epidermis * Slight redness and pain * Immerse burned area in cool water * Second degree burns * Involve epidermis and part of dermis * Skin blistered and painful * Slight scarring Third-degree burns * Involve epidermis, dermis, and subcutaneous layer * Require hospitalization * Treatment for dehydration and infection * Require additional caloric intake * Severe scarring * May need debridement and skin graft * Burn severity can be measured by rule of nines * Estimates surface area of burns

Question 29

what is described in the View: Burns

Answer 29

Treatments for burns * Manage fluid loss * Manage pain * Remove dead tissue * Control infection

Question 30

what are the skin changes from aging

Answer 30

Skin changes with aging * Reduced number and activity of stem cells * Skin repair processes slows * Thin skin less likely to protect from trauma * Fewer collagen fibers * Elastic fibers lose elasticity * Crease lines form (wrinkles) * Immune response decreased due to fewer dendritic cells * Hair follicles produce thinner hair or none at all Smoking and chronic overexposure to UV radiation * Damage DNA in epidermal cells * Accelerates aging * Predominant factor in promotion of skin cancer Skin cancer * Most common type of cancer * Typically on head and neck * Fair-skinned individuals at highest risk

Question 31

what is describe Clinical View: Botox and Wrinkles

Answer 31

Botox is a treatment for wrinkles caused by facial muscle expression * Clostridium botulinum toxin, botulinum toxin Type A * Blocks nerve impulses to facial expression muscles * Decreases or eliminates wrinkles * Botox injected into specific facial muscles * Temporary effect only * Muscles regain function and procedure must be repeated