1B Flashcards
Integumentary System
System of the body compared of the skin and the underlying subcutaneous tissue.
What is the largest organ of the body?
Skin
How much of the body’s total weight does the skin compromise?
15%
Function of the Integumentary System
A. Protection of underlying (barrier to UV light, bacteria, radiation, water).
B. Acts as a site of sensory nerve receptors (pain, heat, cold, touch, pressure).
C. Regulation of body temperature (erect hairs, sweat).
D. Water excretion (sweat).
E. Formation of Vitamin D, which is essential for calcium absorption from the foods we eat.
What 2 layers is the skin composed of?
The epidermis and the dermis.
The epidermis and the dermis lie on an underlying layer called the _______.
Subcutaneous tissue
Sub=below
cutis=skin
Where is the thickest skin located?
back (1/2 cm)
Where is the thinnest skin located?
eyelid (1/2mm)
What is the outermost layer of skin?
The epidermis.
What is the epidermis composed of?
Stratified squamous keratinized epithelium.
The epidermis is avascular but does contain..
Nerve receptors and nerve endings.
The deepest layers of epidermis have cells that undergo..
Mitosis and migrate to the outermost layers, where they become desiccated, convert to keratin, and eventually slough off.
How long does it take for an epidermal cell to go from birth to slough?
30 days- thus, the epidermis (not total skin) is constantly regenerating.
What do the deepest layers of the epidermis contain?
Melanocytes that produce the dark pigment melanin.
What is melanin responsible for?
Skin color, and also protects the individual from the harmful effects of UV light.
Where is the keratin of the epidermis thick?
The palms and soles.
What does the keratin of the epidermis form?
Papillary ridges that occur in characteristic patterns (fingerprints, toe prints).
What is the layer deep to the epidermis?
The dermis.
What is the dermis composed of?
Dense irregular connective tissue, which does contain both blood vessels and nerves.
How thick is the dermis in comparison to the epidermis?
dermis= 80%; epidermis=20%
The dermis has many…
Collagen fibers, sweat glands, and hair follicles.
What is the layer deep to the dermis?
Subcutaneous tissue.
What is the subcutaneous tissue made up of?
Loose connective tissue with an abundance of adipose cells.
What courses its way through the subcutaneous tissue on their way to the dermis?
Blood vessels and cutaneous.
Is the adipose tissue more abundant in males or females?
females.
What does the adipose tissue provide?
Insulation, conserves body heat, and acts as a shock absorber.
Skin is the largest organ in the body, comprising ___ of the total weight of the body.
A. 80% B. 20% C. 3/5 D. 15% E. None of the above
D
The thinnest skin is located on _____.
A. the back of your knee B. your axilla C. subcutaneous tissue D. your eyelids E. none of the above
D
This answer is true in the dermis. Choose all that apply. (if you think the answer is all of the options, then click all 5 options; if you think it is only one or two options, click only those options)
A. It is deep to the epidermis.
B. It is 80% of the thickness of the skin.
C. It contains blood vessels and nerves.
D. It is composed of a dense irregular connective tissue.
E. All of the above.
All of the Above.
Choose the statement(s) that is/are correct.
A. Associated structures are part of the integument that have specific functions.
B. Arrector pilorum muscles are attached to the hair follicle and the epidermal/dermal junction.
C. The epidermis is vascular and contains receptors and nerve endings.
D. a and c
E. a and b
A,B,E
Choose the statement that best describes subcutaneous tissue.
A. It is stratified squamous keratinized epithelium
B. It is loose connective tissue with an abundance of adipose cells.
C. It is dense irregular connective tissue.
D. It contains sweat glands, sebaceous glands, and nerves.
E. None of the above
B
Associated Structures
Structures that are part of the integument that have specific functions.
Hair Follicles
Derived from the epidermis and growing down into the dermis and subcutaneous tissue.
They contain hairs, which form by follicle cells undergoing mitosis.
When a follicle becomes inactive, the hair it produces becomes lost.
Sebaceous Glands
Oil-producing glands that result from disintegration of some gland cells.
Sebum
A duct that passes through this structure into the neck of the hair follicle.
Arrector Pilorum Muscles
Smooth muscles attached to the hair follicle and the epidermal-dermal junction.
Contraction due to cold weather causes the hairs to stand ______ and traps a layer of air within the hairs, which acts as an insulator to keep body heat ______ the body.
Errect; inside
Sweat Glands
Have their secretion part in the dermis and their ducts passing through the epidermis to open at pores on the skin.
Sweat
Water and NaCl; cools the body as it evaporates.
Nails
protective structures of hard keratin located at the tips of fingers and toes.
Your patient has severely low levels of calcium. However, he is ingesting the daily recommended amount, what would explain his condition?
a. A lack of sunlight
b. He is dehydrated, which causes calcium precipitation
c. A low level of vitamin D
d. Calcium is only absorbed when high levels of insulin are present
e. A and C
E
The skin acts as a barrier to microbes, H2O and various organic and inorganic toxins. Which part of the epidermis is responsible for this characteristic?
a. Tight junctions between the epithelial cells
b. Keratinized cuboidal cells
c. Follicular epithelial keratin
d. stratified squamous keratinized epithelium
e. A and D
D
When an injury occurs to the epithelium, how is it repaired?
a. Mitosis directly
b. Binary fission
c. Mitosis at the superficial dermis
d. Mitosis at the basal epithelium
e. Mitosis within the subcutaneous tissue
D
A “sunburn” can occur because of?
a. None of the below
b. Damage to melanocytes
c. damage to papillary ridges
d. Damage to the basement membrane of the subcutaneous tissue
e. damaged melanin
B
The deepest layer of the skin contains all of the following, EXCEPT?
a. Connective tissue
b. nerves
c. Dense irregular connective tissue
d. blood vessels
e. Dense regular/dermal connective tissue
E
A patient presents a deep laceration to the 2nd phalange of the left hand of which bone is now exposed. Which layer will receive nervous damage?
a. Epidermis
b. Dermis
c. Subcutaneous tissue
d. B and C
e. All of the above
E
The following is all true of the layer that is responsible to serve as a shock absorber EXCEPT:
a. it lies immediately deep to the epidermis
b. contains losse connective tissue
c. contains adipose tissue
d. A and C
e. A, B, & C
f. B & C
A
The arrector pilorum muscles attach to the hair follicle and the deep dermis
A. True
B. False
B
