Flashcards in Skin Anatomy Deck (53)
The skin ranges in thickness from __-__ mm
0.5 to 6.0
Where is the thinnest skin located? Where is the thickest skin located?
Eyelids and eardrums
Palms of the hands and soles of the feet
The skin receives about __ of resting cardiac output
What is considered an open wound?
a break in skin integrity (can be as minor as epidermal interruption)
What are the 3 layers of skin?
- hypodermis (subcutaneous connective tissue)
What is the basement membrane?
A thin acellular membrane that anchors the dermis to the epidermis and acts as a scaffolding for the epidermis and a selective filter for substances moving between the 2 layers
Describe what happens to the skin as one ages or is exposed to too much sun?
The basement membrane begins to thin and there is disorganization and loss of collagen fibers
The epidermis ranges in thickness from __-__ mm
0.06 to 0.6 mm
Is the epidermis vascular or avascular?
What are the 5 layers of the epidermis from most superficial to deepest?
- Stratum Corneum
- Stratum Lucidum
- Stratum Granulosum
- Stratum Spinosum
- Stratum Germinativum
What are the 4 types of epidermal cell types?
- Merkel cells
- Langerhans cells
What 2 epidermal cell types serve as protectors?
keratinocytes and Langerhans cells
What epidermal cell type gives the skin its pigment?
What is the function of the Merkel cells?
Describe the structure of the stratum germinativum and what its function is
It is a single row of keratinocytes that continuously divides to produce the protective protein keratin
Describe the structure of the stratum spinosum
it consists of several layers of more mature keratinocytes and appears "spiny" under microscope
Describe the structure of the stratum granulosum
It contains 3-5 flattened cell rows with increasing concentrations of keratin
Describe the structure of the stratum lucidum
It contains a few layers or flattened, dead keratinocytes which appear clear under microscope
Describe the structure of the stratum corneum
It consists entirely of dead keratinocytes
Which layer of the epidermis is the thickest?
Can be as thick as 20-30 cells thick and accounts for up to 3/4 of the epidermis
How long does it take cells to travel from the stratum germinativum to the stratum corneum?
Occasionally there is a localized buildup of cells of the stratum corneum due to pressure or friction, what is this known as?
Describe how Langerhans cells help protect the skin
They fight infection by attacking and engulfing foreign material
The epidermis has 3 appendages located within the dermis, what are they?
- glands (sebaceous and sudoriferous)
Hair follicles are present everywhere except what 2 places?
palms and soles
What is hair composed of and what is its function?
It is composed of soft keratin and helps to regulate body temperature by trapping air between the hair and the skin's surface
Each hair follicle contains what type of gland?
sebaceous gland that secretes sebum
What is sebum?
an oily substance tat lubricates the skin and hair
What do sudoriferous glands secrete?