A&P: Integumentary System Flashcards
What organ and structures make up the integumentary system?
- Skin
- Accessory Structures: hair, nails, glands
What are the two layers of the skin/cutaneous membrane?
- epidermis
- dermis
- (subcutaneous/hypodermis is talked about in integumentary system, but it is NOT a part of the skin)
T/F: The epidermis has a blood supply in which nutrients diffuse from to the dermis
FALSE, the epidermis does NOT have a blood supply, so nutrients will diffuse FROM the dermis
What is the name of the layer below the dermis that contains fat?
hypodermis (subcutanous layer)
not techincally part of skin organ
List 6 functions of the integumentary system
PETSSS
- Protection (from environment)
- Excretion of toxins (water, salt, urea)
- Thermoregulation (maintain temp)
- Synthesis vitamin D
- Sensory Reception
- Secretion of Sebum, sweat, cerumen (ear wax), milk
T/F: The epidermis is vascular
False, the epidermis is avascular, while the dermis and hypodermis are vascular
List 2 ways the integumentary system regulates body temperature
- Sweating (decrease body temp)
- BV at skin surface can dilate and come to surface to give off heat (decrease body temp), or constrict to retain heat (increase body temp)
Define keritinization
process by which cells produce keratin, causing them to harden and become waterproof (->-> will eventually form the stratum corneum)
Epidermis
What do melanocytes do?
produce dark pigment, melanin
Epidermis
What is the fxn of melanin?
protect skin by absorbing UV rays from the sun
Epidermis
Be able to label the layers of the skin
refer to Integumentary notes
Be able to label the layers of the epidermis.
refer to Integumentary notes
Which layer of the epidermis contain melanocytes?
stratum basale
What explains why cells begin to die as you move superficially through the epidermis?
The dermis is vascular and its blood supply nourishes the stratum basale of the epidermis well. However, as you move superficially, the nutrient supply becomes poor, which causes those cells to die.
What explains how cells become tightly packed together as you move superficially through the epidermis?
As cells become older (via keratinization), their cell membranes thicken to create desmosomes (junctions b/w cells that hold them together), which makes them tightly compact and connected to each other
Describe the Epidermis
(Include: Tissue + Cell Type, Layers (Top -> Bottom-most) and include information about each layer: Characteristic of the cells/layers, etc))
Tissue/Cell Type:
- Epithelial Tissue
-> Stratified Squamous
Layers (T -> B): Come, Let’s Get Sun Burnt
-
Stratum Corneum
-> Large amounts of keratin
-> Many layers of flat/dead cells -
Stratum Lucidum (ONLY IN THICK SKIN)
-> Flat, dead cells -
Stratum Granulosum
-> Few slightly flattened cells
-> Keratinocytes begin making keratin -
Stratum Spinosum
-> Several layers of cells connected by desmosomes -
Stratum Basale
-> Single layer of cells attached to BM
-> Form epidermal ridges
-> Contain melanocytes (cytoplasmic extensions reach into upper layers to deliver melanin)
-> Keratinocytes produced via mitosis -> move up layer by layer
Be able to label structures within the dermis through a diagram
refer to Integumenary notes
T/F: The dermis contains capillaries and nerves
True
What is an exocrine gland? Include examples
a gland that releases secretion into a duct or to the surface of the body (ex: sweat and sebaceous glands)
Describe the Dermis
(Include: Tissue + Cell Type, Accessory Structures (include fxn))
Tissue/Cell Type:
Superficial Dermis:
-
Loose CT
-> Collagen Fibers
-> Elastic Fibers
Deep Dermis (these extend into hypodermal layers)
-
Irregular CT
-> Collagen Fibers
-> Muscle Fibers (hair/glands)
Accessory Structures:
- Hair Follicles
-
Sweat glands/Sudoriferious glands (Exocrine glands)
-> Apocrine: secrete product into hair follices of armpits, nipples, groin
-> Merocine/Eccrine: numerous + widely distributed; secrete perspiration -> cool surf of skin -
Sebaceous gland (Exocrine gland)
-> Produce sebum (way oil): lubricate hair and decrease pH -> inhibit bacteria -
Arrector pili muscle (elevates hair)
-> Squeezes sebaceous gland
What is the function of the nail root?
produces the nail
What is the cuticle?
portion of the stratum corneum of the nail root folds/extends over the expose nail nearest to the root
What is known as the body of the nail and the nail plate overlies it?
nail bed
Underlying ______ _______ give the nails its color, but where they are obscured is the pale crescent called the __________
blood vessels
lunula
What happens if the skin has a very shallow cut?
epithelial cells along the margins will be stimulated to divide rapidly to fill in the gaps
What happens if a cut penetrates the dermis (and maybe hypodermis)?
1) Blood vessels will break and blood clots containing fibrin will form
2) Blood clot and dried fluids forms a scab, and epithelial cells below the scab will divide
3) Fibroblasts secrete collagen to bind to wounds edges
4) BV extend below the scab, and phagocytes will remove dead cells/pathogens. If deep, scar tissue will form
Be able to label different parts to the nail
refer to Integumentary notes
What layer of the skin is destroyed/damaged in a 1st degree burn? What sxs does it cause?
- epidermis
- causes redness, pain, minor swelling, NO BLISTERS
What layer of the skin is destroyed/damaged in a 2nd degree burn? What sxs does it cause?
- Some epidermis and some underlying dermis
- Causes more intense redness, pain, swelling, and often blisters
What layer of the skin is destroyed/damaged in a 3rd degree burn? What sxs does it cause?
- Epidermis, dermis, and accessory structures of the skin
- Causes swelling, and skin will appear yellow/brown, and leathery
How does the healing process of a 2nd and 3rd degreen burn differ?
2nd degree:
- healing depends on stem cells associated with accessory strucutres
- Stem cells differentiate and daughter cells grow out onto the surface of the dermis and spread over it and differentiated into a new dermis
3rd degree
- healing ONLY occurs from epidermal cells on the edge of the burn
- can use autograft of epidermis from another part of body
- allograft from cadaver skin/skin substitutes used to cover burn while it heals
A man has a defect in his tyrosinase enzymes, making him have albinism since tyrosinase controls melanin production. What layer of the epidermis is tyrosinase active in?
- Stratum corneum
- Stratum basale
- Stratum lucidum
- Stratum granulosum
stratum basale
What is excreted by sweat glands?
urea
water
salts
Which layer of the skin contains glands and hair follicles?
dermis
