Chapter 5: Integumentary System Flashcards
Integumentary system consists of:
Skin, hair, nails, and sweat glands
Skin has 2 distinct regions:
Epidermis and Dermis
superficial region, avascular
Epidermis
under epidermis, vascular (thick)
- nice and thick
- fibers in matrix bind body together
Dermis
superficial facia, bottom layer of fat
> subcutaneous layer
> Not part of skin
> mostly made of adipose tissue
Hypodermis
Epidermis mostly consist of what type of epithelium
> what is the 4 types of cell in epidermis
Keratinized stratified squamous
> Kertinocytes, Melanocytes, Dendritic, and merkel cells
cells that produced fibrous keratin
Keratinocytes
cells that produces melanin pigment, protect nucleus from UV damage
Melanocytes
cells that has role in immune system
Dendritic (Langerhans) cells
five layers (strata) and is found in palms hands and feet
Thick Skin
Five layers of skin (from inferior to superficial)
Stratum basale,
Stratum spinosum,
Stratum granulosum,
Stratum lucidum (thick skin)
Stratum corneum
deepest layer of the skin, firmly attached to dermis.
Stratum basale (basal layer)
prickly layer of the skin, appears spikey with several cell layers
Stratum spinosum (prickly layer)
four to six cell layers of skin, but cells are flat (so it is thin)
Stratum granulosum
layer of skin found on palms of hands and soles of feet, has dead cells.
Stratum lucidum (clear layer)
layer of skin with 20-30 rows of flat anucleated, keratinized DEAD cells
Stratum corneum
cells change by going through _____ (controlled cell death)
Apoptosis
The Dermis consists of 6 things:
nerves, blood vessels, and lymphatic cells.
Also epidermal hair follicles, oil glands, and sweat glands
what are the two types of connective tissues in the dermis?
papillary(loose areolar) and reticular (dense irregular CT)
This is a superficial layer of loose areolar connective tissue consisting of collagen and elastic fibers in the dermis
- also projections contains capillary loops, free nerve endings and touch receptors.
Dermal papillary layer
This dermal layer consists of 80% of dermal thickness, and consists of elastic fibers and collagen fibers
Reticular layer
striae aka stretch marks are an example of _____.
What are skin traumas that are fluid-filled pockets that separate epidermal and dermal layers?
dermis tears
Blisters
What three pigments contribute to skin color
Melanin, Carotene, and Hemoglobin
What provides skin protection from UV damage and is also a pigment that contributes with skin color
Melanin
What skin pigment provides yellow to orange pigment and is most obvious in the palms and soles of hands and feet.
- can also be converted to vitamin A for vision and epidermal health
Carotene
What three pigments contribute to skin color
Melanin, Carotene, and Hemoglobin
What pigment shows up more when there is lower levels in melanin (in caucasians)
and is considered protein in the skin
Hemoglobin
Blue skin color bc of low oxygen in hemoglobin?
pale color bc of anemia, low blood pressure, fear, and anger?
redness caused by fever, hypertension, inflammation, and allergies?
yellow cast caused by liver disorders?
Cyanosis
Pallor
Erythema
Jaundice
hair consists of _______, and is aka _____.
dead keratinized cells
Pilo
What are the 2 regions of hair?
What are the three parts of the hair shaft?
Regions: Shaft (above scalp), Root (within scalp)
parts of hair shaft:
Medulla (core of large cells), Cortex (layers of flat cells), Cuticle (outer layer of single cells)
What are the parts of a hair follicle?
Hair bulb - deep end of follicle
> Hair matrix: actively dividing area that makes hair cells.
Hair follicle receptor - sensory nerve endings around bulb
Arrector pili - muscle attached to hair
what are the two types of hair growth?
Vellus hair - pale, fine body hair of childern and adult females
Terminal hair - coarse, long hair, found on scalp and eyebrows
> during puberty -> appears in axillary and pubic regions
What is excessive hairiness?
(can be a sign of masculinization)
Hirsutism
What condition is some degree of hair loss
Alopecia
What is a scale like modification of epidermis that contain hard keratin and acts s protection for fingers and toes?
Nails
Nails consists of:
free edge, nail plate, and root
part of nails that is epidermis underneath keratinized nail plate
Nail bed
thickened portion fo bed responsible for nail growth?
Nail matrix
part of nail that is a thickened nail matrix, appears white, and near the cuticle
(cardiovascular and nervous)
Lunule
nail fold that projects onto surface of nail body also known as cuticle
Eponychium
area of the nail under free edge plate that accumulates dirt
Hyponychium
yellow nails can be due to _____
concavity of nail that may signal iron deficiency (aka spoon nail) is _______
when nails appear convex like clubs, can sometimes indicate respiratory and cardiovascular diseases.
fungal infection of nail
Koilonchya
Clubbing
almost all skin surfaces contain sweat glands aka _______
what are the two main types?
sudoriferous glands
> eccrine (merocine) sweat glands
apocrine sweat glands
Most numerous type of sweat glands
- has function in thermoregulation
Eccrine (merocrine) sweat glands
found in armpit (axillary) and anus (anogenital) areas
- secretes sweat containing fatty substances and proteins
-bacteria break down sweat = body odor
- ducts located emptying into hair follicles
- begins to work at puberty
Apocrine sweat glands
Modified apocrine glands types:
Ceruminous glands (external ear canal; secretes earwax)
Mammary glands (secrete milk)
- most develop from hair follicles, and secrete into hair follicles
- secretes sebum, (hormones: acne)
Sebaceous (oil) glands
an infectious inflammation of sebaceous glands, resulting in pimples
blocked sebaceous glands
overactive sebaceous glands in infants can lead to…
Acne
Whiteheads
seborrhea
6 functions of Skin
protection
body temp regulation
cutaneous sensations (to feel)
metabolic functions
blood reservoirs
excretion of wastes
skin is exposed to microorganisms, abrasions, extreme temps, and harmful chemicals
constitutes 3 barriers:
Protection
Chemical barrier
physical barrier
biological barrier
skin barrier with sweat, oil, low pH, melanin, and defensins
Chemical barriers
skin barrier with Keratinized cells
Physical barriers
skin barrier with dendritic cells (APC) of epidermis, macrophages of dermis, DNA absorbs UV light
Biological barriers
with resting body temp, sweat glands produce unnoticeable sweat called ____
insensible perspiration
If body temp rises, dermal vessels can increase sweat gland activity to produce 12 L of noticeable sweat called ____ which is designed to cool the body
sensible perspiration
cutaneous sensory receptors are….
part of nervous system
extreroreceptors responds to stimuli outside body, such as temp and touch
free nerve endings that sense painful stimuli
skin metabolic functions
- synthesize vitamin D for calcium absorption in intestine
- makes collagnase, aids in natural turnover of collagen to prevent wrinkles
skin Blood reservoir
- hold up to 5% of body’s blood volume
- vessels can be constricted to shunt blood to other organs (excercising muscle)
three types of skin cancer
basal cell carcinoma
squamous cell carcinoma
Melanoma
basal cell carcinoma
malignant and most common
- stratum basale cells proliferate and slowly invade dermis and hypodermis
- cured by mostly by surgical excision
squamous cell carcinoma
second most common type, can metastasize
- keratinocytes of stratum spinosum
- usually scaly red papule on scalp, ears, lower lip, or hands
- can be treated with radiation therapy or surgical removal
Melanoma
-cancer in melanocytes, most dangerous bc is easily spreads and is resistant to chemo
- can be treated with surgical excision + immunotherapy
Burns
tissue damage caused by heat, electricity, radiation, or certain chemicals
- immediate threat is dehydration and electrolyte imbalance
1st degree burn
localized redness, edema(swelling), and pain
2nd degree burns
epidermal and upper dermal damage
-blisters appear
3rd degree burns
-through epidermis, dermis, and hypodermis (entire thickness of skin)
- skin color turns gray-white, cherry red or blackened
-No edema seen and area is not painful bc nerve endings are destroyed
- skin grafting usually necessary
