Ch 5 The integumentary system Flashcards
Integumentary system
Is the largest system of the body and has two major parts that cutaneous membrane or your skin and the accessory structures which include hair exocrine glands and nails for example
What are the two major parts of the integumentary system
Cutaneous membrane
Accessory structures
The components of the cutaneous membrane
Are the outer epidermis
In the inner epidermis
Accessory structures
Originate in the dermis and expand through the epidermis to the skin surface
For example hair and hair follicles, exocrine glands, nails
Subcutaneous layer / hypodermis
Is below the dermis and made of loose connective tissues
This is where blood vessels and send through receptors are
Thin skin
Covers most of the body and has four layers of keratinocytes
It is about as thick as a plastic sandwich bag
Thick skin
Covers the palms of the hands and soles of the feet
It has five layers of keratinocytes and is about as thick as a paper towel
What are the five strata (layers) of keratinocytes in thick thick skin
From deepest to most superficial
Stratum basale
Stratum spinosum
Stratum granulosum
Stratum lucidum
Stratum corneum
Stratum Basale (stratum germinativum)
This is the deepest basal layer of the epidermis it attaches to the basement membrane forming a strong bond between epidermis and dermis
Stratum spinosum/ the spiny layer
Cells in this layer look like little pin cushions 8 to 10 layers of keratinocytes bound by desmosomes they are produced by cells division in the stratum Basel in contain dendritic cells which are active in immune response
Stratum granulosum
The granular layer there are three to five layers of keratinocytes produced from cells of the stratum spinosum by the time cells enter this layer most have stopped dividing and have started making large amounts of keratin
After production of protein these cells die
Stratum lucidum slash the clear layer
This is found only in thick skin and covers the stratum granulosum the cells are flat and densely packed mostly without organelles and fiied with keratin
Stratum corneum / the horny layer
It’s the exposed surface of skin both in thick and thin layers it is water resistant and 15 to 30 layers of keratinized cells new cells move from stratum basal to stratum corneum and 7 to 10 days
Exposed cells are shed after how many weeks
Two
How long does it take new cells to move from the stratum Basel to the stratum corneum
7 to 10 days
Insensible perspiration
Evaporative water loss by diffusion across the epithelium of skin or evaporative across the alveolar surface of the lungs
Sensible perspiration
Water loss due to secretion by sweat glands
What happens when damage breaks connections between superficial and deeper layers of the epidermis
It can increase the rate of insensible perspiration fluid accumulates in pockets also called blisters
Dermis
Located between epidermis and subcutaneous layers of skin
This layer anchors the epidermal accessory structures such as hair follicles and sweat glands
Cutaneous plexus
Deep network of arteries along the reticular layer of the dermis
Sub papillary plexus
Network of small arteries in the papillary layer of the dermis
Subcutaneous layer/hypodermis
This layer lies deep to the dermis connected to reticular layer by connective tissue it’s stabilizes the position of the skin
What two pigments influence the color of skin in the epidermis
Melanin and carotene
Melanin
Melanin is produced by melanocytes stored in intercellular vesicles called melanozomes red/yellow or brown / black pigment.
Dark skinned people have a large and numerous amount of melanosomes these protect the skin from ultraviolet radiation
