Integumentary System - Functions Of Skin Flashcards
Skin is ____ and foremost a _______ .
First
Barrier
Skins main functions include:
- protection
- body temperature regulation
- cutaneous sensations
- metabolic functions
- blood reservoir
- excretion of wastes
Skin constitutes three barriers:
Chemical barrier
Physical barrier
Biological barrier
Skin secretes many chemicals such as:
Sweat
Sebum
Defensins
Sweat contains . . .
Antimicrobial proteins
Sebum & defensins kills _________ .
Bacteria
Acid mantle is ____________ of skin retards _____________________ .
Low pH
Bacterial multiplication
_________ provides a _________ barrier against UV radiation damage.
Melanin
Chemical
Physical barrier is made up of _______, ______, __________ cells of ____________, surrounded by __________, block most ______ and ______________ substances.
Flat, dead, keratinized
Stratum corneum
Biological barrier is ___________ which contains ___________ cells.
Epidermis
Phagocytic
Dermis contains ___________ . They also activate _______________ by presenting foreign antigens to white blood cells.
Macrophages
Immune system
_______ can absorb harmful UV radiation, converting it to harmless heat.
DNA
Under normal, resting body temperature, sweat glands produce about ____________ of unnoticeable sweat.This is called ____________ .
500 ml/day
Insensibleperspiration
If body temperature rises, dilation of dermal vessels can increase sweat gland activity to produce _________ of noticeable sweat. This is called _____________________ .
12 L (3 gallons)
Sensible perspiration
In cold external environment dermal blood vessels _________ .
Constrict
____________________ receptors are part of the nervous system.
Cutaneous sensory
__________ respond to stimuli outside body, such as _________ and ______ .
Exteroreceptors
Temperature
Touch
___________________ sense ________ stimuli.
Free nerve endings
Painful
Skin can synthesize vitamin ______ needed for calcium absorption in intestine.
Vitamin D
Chemicals from _________ can disarm some ___________ .
Keratinocytes
Carcinogens
_________ can activate some ____________ .
Keratinocytes
Hormones
Skin makes _____________, which aids in natural turnover of _______ to prevent __________ .
Collagenase
Collagen
Wrinkles
Skin can hold up to ______ of the body’s total blood volume.
5%
Skin vessels can be ________ to shunt blood to other ____, such as an __________ muscle.
Constricted
Organs
Exercising
Skin can secrete limited amounts of _________________, such as _______, ______, and ______________ .
Nitrogenous wastes
Ammonia, urea, and Uric acid
Sweating can cause _____ and ______ loss
Salt and water
Less common, but more damaging skin developments are:
Skin cancer
Burns
Most skin tumors are _______ and do not ________.
Benign
Metastasize
Risk factors of skin cancer:
Overexposure to UV radiation
Frequent irritation of skin
three major types of skin cancers are:
Basal cell carcinoma
Squamous cell carcinoma
Melanoma
Basal cell carcinoma is _______ malignant and ______ common.
Least
Most
In basal cell carcinoma _____________ cells proliferate and slowly invades _______ and ____________ .
Stratum basale cells
Dermis & hypodermis
Cured by _______________ in 99% of cases.
Surgical excision
Squamous cell carcinoma is ___________ common; can _________.
Second most
Metastasize
Squamous cell carcinoma involves __________ of ______________ .
Keratinocytes
Stratum spinosum
Usually is a scaly reddened papule on ______, ____, __________ or ______ .
Scalp, ears, lower lip or hands
Squamous cell carcinoma is treated by __________ or __________ .
Radiation therapy
Removed surgically
Melanoma is the cancer of ___________ and is the most dangerous type because . . .
Melanocytes
It is highly metastatic & resistant to chemotherapy
Melanoma - ABCD rule :
A - asymmetry
B - border
C - color
D - diameter
Burns are tissue damage caused by _____ , _________, _________, or ________________ .
Heat
Electricity
Radiation
Certain chemicals
Immediate threat to burns is _________ and _________________. Which can lead to ________ and _________________ .
Dehydration and electrolyte imbalance
Renal shutdown and circulatory shock
Burns can be classified by __________ .
Severity
Superficial burns are ____________ only
Epidermal damage
Superficial partial-thickness / deep partial thickness burns are _________ and _____________ damage. ________ appear.
Epidermal and upper dermal
Blisters
Full thickness burns are entire thickness of skin involved through the ___________ tissues. Area is not painful because __________ are destroyed.
Subcutaneous
Nerve endings
Burns are considered critical if:
> 20% of body has deep-partial thickness burns
10% of body has full thickness burns
Face, hands, or feet bear full thickness burns
Burn treatment includes:
Debridement
Antibiotics
Temporary covering
Skin grafts
Development of Skin - Fetal: by end of ___ month, skin of fetus is developed.
4th
Lanugo coat:
Delicate hairs in 5th and 6th month
Vernix caseosa:
Sebaceous gland secretion that protects skin of fetus while in watery amniotic fluid
Infancy to adulthood: skin ________ and accumulates more ________________; sweat and sebaceous gland activity ________, leading to ______.
Thickens
Subcutaneous fat
Increases
Acne
In aging skin _____________ slows; skin becomes ______, ____, and ________.
Epidermal replacement
Thin, dry, and itchy
In aging skin subcutaneous fat and elasticity ________, leading to ___________ and _________.
Decrease
Cold intolerance and wrinkles
The skin plays a role in the manufacture of vitamin ______.
a) A
b) B
c) C
d) D
D) D
What is the immediate threat from severe burns?
A) Bacterial infection
B) Inadequate body temperature maintenance
C) Loss of water and electrolytes
D) Scarring
C) Loss of water and electrolytes
Which of the following types of skin cancer is the most dangerous?
A) Basal cell
B) Squamous cell
C) Melanoma
D)All are equally dangerous.
C) Melanoma
Which of the following is not true for the skin in old age?
A) It is less susceptible to bruising
B) The rate of epidermal cell replacement slows
C) The skin thins
D) Secretions from glands decrease
A) It is less susceptible to bruising
