Ch 6: Integumentary System Flashcards
Exam 2 Review
The integumentary system consists of
- skin
- hair
- nails
- cutaneous glands
The scientific study and medical treatment of the integumentary system is known as…
Dermatology
Name the 3 layers of skin.
- epidermis
- dermis
- hypodermis
In what layer of the skin are shots given?
hypodermis
What is the piloerector muscle responsible for?
raising a hair to stand on end
In what layer of skin is the bulb of a hair found?
dermis
Thick skin is located where?
- palms of hand
- soles of feet
- well used finger and toe surfaces
The skin absorbs what vitamin?
D
Vitamin D helps us to absorb…
Calcium
What are the four functions of skin?
- Sensation
- Thermoregulation
- Nonverbal communication
- Transdermal absorption
What is the epidermis made of?
keratinized stratified squamous epithelium
What are the five types of cells in the epidermis?
- Stem cells
- Keratinocytes
- Melanocytes
- Tactile (or Merkel) cells
- Dendritic (or Langerhans) cells
Tactile cells are also known as _______ cells
merkel
Dendritic cells are also known as _______ cells.
Langerhans
Characteristics of stem cells:
- undifferentiated cells that give tise to keratinocytes
- in deepest layer of epidermis (stratum basale)
Characteristics of keratinocytes:
- great majority of epidermal cells
- synthesize keratin
Characteristics of tactile/merkel cells:
- in basal layer of epidermis
- touch receptors associated with dermal nerve fibers
What are the 5 layers of the epidermis (top to bottom)?
- stratum corneum
- stratum lucidum
- stratum granulosum
- stratum spinosum
- stratum basale
Characteristics of stratum basale:
- single layer of cuboidal or columnar stem cells and keratinocytes resting on basement membrane
- Melanocytes and tactile/merkel cells are scattered throughout this layer
Stem cells of stratum basale divide to…
- give rise to keratinocytes that migrate toward skin surface
- replace lost epidermal cells
Characteristics of stratum spinosum:
- produce keratin filaments which flattens cells as they migrate up.
- layer where dendric/langerhans cells are found
- thickest stratum of epidermis
- deepest cells capable of mitosis
Characteristics of stratum granulosum:
- consits of three to five layers of flat keratinocytes
- contains dark-staning keratohyali granules
Characteristics of stratum lucidum:
- only found in thick skin
- cells have no nucleus or other organelles (no translation)
Keratinocytes are produced by _____ _____ in the stratum _______.
stem cells, basale
Mitosis requires an abundant supply of…
oxygen and nutrients.
In __ - ___ days, a keratinocyte makes its way to the skin surface and flakes off.
30-40
Water retention is important in preventing _______.
dehydration
What items are found in the dermal layer of skin?
- blood vessels
- glands
- nerve endings
- piloerecter muscles
- hair follicles and nail rooted
What are dermal papillae?
protrusions from dermis up into the epidermis layer to provide nutrients
The papillary layer is made of what type of tissue
areolar
What are the two layers of the dermis?
- papillary layer
- reticular layer
The reticular layer consists of what kind of tissue?
dense irregular connective tissue
Characteristics of hypodermis:
- made of areolar and adipose tissue
- layer for injections
- pads body
- binds skin to underlying tissues
Characteristics of subcutaneous fat:
- energy reservoir
- thermal insulation
- 8% thicker in women
Eumalanin =
brownish black
Pheomelanin =
a reddish yellow sulfur-containing pigment
True or False
People of different skin colors have the same number of melanocytes.
TRUE
Chacteristics of melanin in dark-skinned people:
- produce greater quantities of melanin
- melanin breaks down more slowly
- melanized cells seen throughout the epidermis
- melanin granuales spread out
Chacteristics of melanin in light-skinned people:
- melanin clumped near keratinocyte nucleus
- melanin breaks down more rapidly
Red pigment of red blood cells is called
hemoglobin
A yellow pigment concentrated in stratum corneum and subcutaneous fat is called
Carotene
Blueness of skin from dificiency of oxygen in the circulating blood
Cyanosis
Abnormal redness of skin due to dialated cutaneous vessels is called
Erythema
Causes of erythema
- exercise
- hot weather
- sunburn
- anger
- embarrassment
Causes of cyanosis
- airway obstrcuction
- lung diseases
- cold weather
- cardiac arrest
Pale or ashen color when there is little blood flow through skin and the whtie color of dermal collagen is visible refers to
Pallor
Causes of pallor:
- emotional stress
- low blood pressure
- circulatory sock
- cold
- anemia
A genetic lack of melanin that results in white hair, pale skin and pink eyes
Albinism
Cause of albinism:
Inherited recessive, nonfunctional tyrosinase allele
What are causes of jaundice and how does it manifest?
- cancer
- hepatitis
- cirrhosis
- compromised liver function
- presents by a yellowing of the skin
Hematoma:
- mass of clotted blood showing through skin
- also called a bruise
The varied manifestation of skin color in humans was caused by
- geographic location and exposure to ultraviolet radiation
- northern/southern folk = lighter skin
- equatercentric folk = darker skin
What are two adverse effects of UVR?
- skin cancer
- breaks down folic acid needed for mitosis, fertility and fetal development
In what way is UVR positive?
stimulates synthesis of vitamin D
True or False
Altitude and dry air have nothing to do with skin pigmentation.
False
Andes, Tibet, Ethiopia peeps have darker skin than their lowland kin.
UVR accounts for up to __% of variation in human skin color
77%
What are some other modern causes of variations in skin color?
- migration
- intermarriage
- darwinian sexual selection (pref of complexion in mate)
Friction ridges are also known as…
fingerprints
Friction ridges allow for…
the manipulation of small objects
Flexion lines are found…
where the skin folds during flexion of the joints
(fingers, elbows, etc)
Hemangiomas are also known as…
birthmarks
Flat, melanized patches on the skin are called
Freckles
Elevated melanized patches (often with hair) are called
moles
Moles should be wached for…
why?
changes in color, diameter or contour
may be skin cancer
Patches of discolored skin caused by benign tumors of dermal blood capillaries are called a
Hemangioma or birthmark
The accessory organs of the skin are:
- hair
- nails
- cutaneous glands
Hair and nails are composed of mostly
dead, karatinized cells
Soft keratin makes up
stratum corneum of skin
Hard keratin makes up
hair and nails
What are the 3 kind of hair?
- Lanugo
- Vellus
- Terminal
Characteristics of lanugo hair
fine downy fetal hair that appears in the last 3 months of development
Characteristics of vellus hair
- fine, pale hair that replaces lanugo by birth
- two-thirds of hair on women (arm hair, etc)
- 1/10th of hair on men (in bald areas of the head)
- All hair of children except eyebrows, eyelashes and scalp
Characteristics of terminal hair
- longer, coarser, darker hair
- eyebrows, lashes, scalp
- after puberty: auxillary (pits) and pubic hair
- male facial hair and some on trunk and limbs
Name and give brief description of the 3 parts of a hair.
- Bulb - swelling at the base in dermis or hypodermis. Only area that contains living hair cells
- Root - the remainder of the hair between bulb and surface
- Shaft - visible portion above the skin
Brown and black hair is rich in
eumelanin
Red hair has a slight amount of _______ but a high concentration of ______.
eumelanin, pheomelanin
Blonde hair has an intermediate amount of _______ and very little _______ .
pheomelanin, eumelanin
Gray and white hair results from scarcity or absence of _______ in the cortex and the presence of _______ in the medulla.
melanin, air
Regarding hair texture:
- Straight hair is
- Wavy hair is
- Curly hair is
- round
- oval
- relatively flat
Hirsutism:
excessive hairiness in areas that are not usually hairy
The nail plate is made of:
- free edge
- nail body
- eponychium (cuticle)
The nail root is the part that
goes under the skin at the bottom.
The nail fold is the area
where the nail and flesh of finger meet
The lighter color at the base of the nail is called the
lunule
Sweat is primarily a
protein-free filtrate of blood plasma
The acidity of sweat or acid mantle does what?
inhibits bacterial growth
Insensible perspiration
does not produce visible wetness of skin
(500 mL/day)
Diaphoresis:
sweating with wetness of skin
(may lose 1 L of sweat per hr)
Sebum:
Oily secretion produced by sebaceous glands
Holocrine gland secrtion consists of…
broken down cells
Ceruminous glands produce..
Cerumen (earwax)
Purpose of cerumen?
- Keeps eardrum pliable
- Waterproofs the canal
- Kills bacteria
- Makes hairs of ear sticky to block foreign particals from entering
Prolactin is the…
hormone to produce milk
Expression of milk is encourged by
oxytocin
Three types of cancer:
- basal cell carcinoma
- squamous cell carcinoma
- malignant melanoma
Characteristics of first degree burn:
- partial thickness burn
- involves only epidermis
- marked by redness and soreness
- ex. sunburn
Characteristics of second degree burn:
- involves epidermis AND part of dermis
- leaves part of dermis intact
- red, tan or white
- two weeks to several months to heal. May leave scar
- blistered, painful
Characteristics of third degree burn:
- full-thickness burn
- effects epidermis, all of dermis and some deeper tissues (muscles or bones) are destroyed
- often requires skin grafts
- needs fluid replacement and infection control
Autograft:
tissue taken from another location on the same person’s body
Isograft:
skin from identical twin
Homograft:
skin from unrelated person
Heterograft:
skin from another species or amnion from afterbirth
What kind of gland secretes hormones?
endocrine
Melanin is the most significant factor in
skin color
Melanin is produced by
melanocytes
Melanin is spread throughout the keratinocytes of which layers of the epidermis?
Strutum spinsosum and basale
In what stratum of the epidermis are melanocytes located?
stratum basale
Melanin shields _______ from _______.
DNA, UVR
Dendritic/langerhans cells are located in which stratum of the epidermis?
granulosum and spinosum
Epidermal cells that attack pathogens and bacteria are called
dendritic/langerhans cells
Basal cell carncioma
Forms from cells in what stratum?
Basale
Characteristics of a leasion of basal cell carcinoma are
small, shiny bump with a central depression
True or False
Basal cell carcinoma is the least common and most dangerous type of skin cancer.
FALSE
It is the most common and least dangerous.
Squamous cell carcnioma forms from what cells in what stratum of the epidermis?
keratinocytes of the stratum spinosum
A leasion of squamous cell carcinoma has
raised, reddened, scaly appearance later forming a concave ulcer
Squamous cell carcinoma has a good chance of recovery with _______ detection and _______ removal.
early, surgical
Malignant melanoma effects what cells?
melanocytes
Can melaignant melanoma be treated?
Surgically yes, if caught early
True or False
Malignant melenoma is the most common and least dangerous type of skin cancer.
False
it is the least common and most dangerous
Malignant melanoma _______ rapidy and is unresponsive to _______ chemo therapy.
The stratum _______ exfoliates over time.
corneum
What is the primary layer of the epidermis that is resistnt to abrasion, penetration and water loss?
Stratum Corneum
Which layer of epidermis has up to 30 layers of dead keratinized cells?
Stratum corneum
