Integumentary System

Question 1

Tissue in epidermis

Answer 1

Keratinized stratified squamous epithelial

Question 2

Tissue in dermis

Answer 2

fibrous connective tissue

Question 3

Layers in epidermis

Answer 3

Stratum Corneum
Stratum Lucidum
Stratum Granulosum
Stratum Spinosum
Stratum Basale

Question 4

Cells in epidermis

Answer 4

Keratinocytes - most cells of epidermis, produce keratin, arise from basal layer
Melanocytes - 10-25% of cells in deepest epidermis, produce melanin (pigment), protect from UV
Dendritic langerhans cells - macrophages
Tactile cells (sensory)

Question 5

Stratum Corneum

Answer 5

Superficial, 20-30 layers, protect deeper cells from environment and water loss, protect from abrasion and penetration

Question 6

Stratum Lucidum

Answer 6

visible only in thick skin, just deep to stratum corneum, superficial to stratum granulosum, dead keratinocytes

Question 7

Stratum Granulosum

Answer 7

thin - 4-6 layers, cells flatten, nuclei and organelles disintegrate, keratinization begins. cells accumulate granules (keritahyaline (help form keratin) granules & lamellar (water resistant to slow water loss across epidermis). cells above this layer are too far from dermal capillaries and die.

Question 8

Stratum Spinosum

Answer 8

several layers thick, contain web-like system of intermediate pre keratin filaments attached to desmosomes, abundant melanosomes and dentritic cells.

Question 9

Stratum Basale

Answer 9

Deepest epidermal layer, also called germinative (highly mitotic). firmly attached to dermis. single row of stem cells. produces 2 daughter cells, 1 goes to surface, 1 remains in basal layer to continue reproducing.

Question 10

3 pigments that contribute to skin color

Answer 10

1. Melanin - only pigment made in skin, reddish-yellow to brownish-black, produced in melanocytes (same # in all ppl), migrates to keratinocytes to form pigment shields for nuclei. sunspots = not melanin, it’s fungus infection. freckles & pigmented moles are local accumulations of melanin. sun exposure stimulates melanin production
2. Carotene - yellow to orange pigment, obvious in soles + palms. accumulates in stratum corneum + hypodermis. converts to vitamin A for vision and epidermal health
3. Hemoglobin - pinkish hue of fair skin

Question 11

arrector pili muscle

Answer 11

smooth muscle attached to follicle, responsible for goose bumps

Question 12

dermal papilla

Answer 12

superficial peglike projections in papillary layer of dermis, contain capilary loops, contribute to pain + touch.

Question 13

hair papilla

Answer 13

protrudes into the hair bulb, contains knot of capillaries that supplies nutrients to the growing hair and signals it to grow

Question 14

hair follicle

Answer 14

• extends from dermis to epidermal surface.
  
  • has a 2 layered wall - part dermis, part epidermis
  • hair bulb = deep end. contains hair papilla (capillaries) and sensory nerve endings.
  • wall is composed of peripheral tissue sheath (dermis) and epithelial root sheath (epidermis).
  • hair matrix produces hair cells, pushes upward
  • arrector pili - muscle that causes goosy bumps

Question 15

Keratinocyte

Answer 15

produce fibrous protein keratin, which forms most of the epidermis. tightly connected by desmosomes.

Question 16

keratin

Answer 16

fibrous protein that helps give epidermis its protective properties.

Question 17

keratinization

Answer 17

epithelial cells turn to keratin.

Question 18

melanocyte

Answer 18

spider shaped epithelial cells that synthesize the pigment melanin, found in stratum basale

Question 19

melanin pigment

Answer 19

• only pigment made in skin,
  
  • reddish-yellow to brownish-black,
  • produced in melanocytes (same # in all ppl),
  • migrates to keratinocytes to form pigment shields for nuclei.
  • sunspots = not melanin, it’s fungus infection.
  • freckles & pigmented moles are local accumulations of melanin.
  • sun exposure stimulates melanin production

Question 20

Cyanosis

Answer 20

Blue skin color, low oxygenation of hemoglobin

Question 21

Erythema

Answer 21

Redness - fever, hypertension, inflammation, allergy

Question 22

Pallor (blanching)

Answer 22

paleness - anemia, low blood pressure, fear, anger

Question 23

jaundice

Answer 23

yellowing - liver disorder

Question 24

Bronzing

Answer 24

inadequate steroid hormones in addison’s disease

Question 25

Bruises

Answer 25

clotted blood beneath skin

Question 26

hair regions

Answer 26

medulla - central core, consists of large cells and air spaces. contains soft keratin, absent in fine hairs. cortex - bulky layer surrounding medulla, consists of several layers of flattened skin. cuticle - outermost layer, single layer of cells, looks like shingles.

Question 27

hair pigment

Answer 27

melanocytes at the base of the hair follicle, transferred to the cortical cells. various proportions of melanins of different colors combine to produce hair from blonde to black. red hair = iron containing pigment. when melanin production decreases and air bubbles replace melanin in the hair shaft, hair turns gray or white.

Question 28

distribution of hair (vellus vs terminal)

Answer 28

``` vellus = fine, pale. body hair of children and adult females. terminal = coarser, longer. eyebrows, scalp. @ puberty, in axillary and pubic regions, and on face and chest of men. ```

Question 29

growth of hair

Answer 29

follicles cycle between active and regressive phases. average 2.25 mm growth per week, and loss of 90 scalp hairs daily. during regressive phase, hair matrix cells die and follicle base and hair bulb shrivel. hair falls out and a new hair grows.

Question 30

alopecia

Answer 30

hair thinning. terminal hairs are replaced by vellus hairs, and hair becomes wispier. happens after age 40

Question 31

true frank balding

Answer 31

aka male pattern baldness, genetically determined, sex-influenced condition. changes the response of the hair follicles to testosterone, and growth cycles become so short, the hair never makes it out of the follicle before shedding.

Question 32

structure of nails

Answer 32

* scalelike modifications of epidermis, * protective cover for distal, * dorsal surface of fingers and toes. * contains hard keratin * nail matrix is responsible for growth

Question 33

location, how many per person, types of sweat glands, and their structure

Answer 33

* all over body except nipples and parts of external genitalia. * up to 3 million per person. * eccrine + apocrine * function of secretion: thermoregulation

Question 34

structure and location of sebaceous glands

Answer 34

* widely distributed except in palms and soles. * develop from hair follicles and secrete into hair follicles * remain inactive until puberty * secrete sebum * bacterial, softens hair & skin

Question 35

eccrine vs apocrine sweat glands

Answer 35

eccrine - abundant on palms, soles, forehead. simple, coiled, tubular gland. secretory part lies coiled in dermis, and duct extends to open in a pore at the skin surface. --secretion = sweat. apocrine - in axillary and anogenial areas. larger, ducts empty into hair follicles. secrete sweat and fatty substances and proteins. --ear wax & milk from mammary glands. begin to function @ puberty

Question 36

Functions of Integumentary System PBCMBE

Answer 36

1. Protection 1. chemical - sebum + defensins, low PH retard bacterial multiplication; melanin 2. physical - thickness of skin, keratin & glycolipids block most water 3. biological - dendritic cells of epidermis, macrophages in dermis, DNA absorb UV radiation and turns it to heat 2. Body Temp Regulation - if temp rises, dilate dermal vessels and increase sweat activity. if temp lowers, capillaries constrict, skin temp drops to slow passive heat loss 3. Cutaneous sensation - detect temp, touch, pain 4. Metabolic functions - synthesize vitamin D and collagenase, convert carcinogens and activate some hormones. 5. Blood reservoir - up to 5% of body's blood volume 6. Excretion - nitrous wastes + salt in sweat.

Question 37

Skin cancers

Answer 37

Basal cell carcinoma - least malignant, most common. stratum basale cells grow and invade dermis & hypodermic. can be removed surgically. Squamous cell carcinoma - second most common type, involves keratinocytes of stratum spinosum. scaly reddened papule on scalp, ears, lower lip, hands. does metastasize. can be removed with radiation therapy or removed surgically Melanoma - most dangerous, cancer of melanocytes. highly metastatic and resistant to chemotherapy. people usually die. ABCD -- asymmetry, border irregularity, color (contains several), diameter (6mm)

Question 38

why are burns life threatening?

Answer 38

* catastrophic loss of body fluids containing proteins and electrolytes - causes dehydration and electrolyte imbalance, renal failure, circulatory shock (inadequate blood circulation due to reduced blood volume) * also need thousands of extra food calories to replace lost proteins and allow for tissue repair. * infection

Question 39

rule of nines

Answer 39

``` head = 9% upper limbs = 18% trunk = 36% perineum = 1% lower limbs = 36% ```

Question 40

Severity of burns

Answer 40

1st degree: only epidermis is damaged. redness, swelling pain. heal within 2-3 days. (sunburn) 2nd degree: epidermis and upper region of dermis is damaged. like 1st degree + blisters. 3rd degree: full thickness burns, involving entire thickness of skin. burned area is gray-white, cherry red, or blackened. nerve endings are not painful. needs skin grafting.

Question 41

Critical % of burns

Answer 41

25% of body has second degree burns 10% of body has third degree burns There are third degree burns of face, hands, and feet.

Question 42

decubitus ulcers / bedsores

Answer 42

results from pressure or pressure in combination with shear and or friction. occurs in sacrum, coccyx, heels or hips, but can also occur elbows, knees, ankles, or back of the cranium. pressure applied to soft tissue so that blood flow to the soft tissue is completely or partially obstructed.