epidermis Flashcards
integumentary system
Epidermis
- Protecting the body from the outside as the outermost layer
- keeping your skin hydrated
- producing new skin cells
- determining your skin color
Dermis
- The middle layer of skin
- contains collagen, blood vessels, glands, hair follicles, and nerve endings
- support and protect the skin
- aid in sensation and thermoregulation
Hypodermis (subcutaneous)
- The innermost layer of skin
- storing energy
- connecting the dermis layer of your skin to your muscles and bones
- insulating your body
- protecting your body from harm.
Dermal papillae
Regulate hair growth, protrusions of dermal connective tissue into the epidermal layer.
Melanocytes
produce and distribute melanin, which is a skin pigment.
Stratum corneum
First line of defense against the environment.
* the most superficial layer of the epidermis.
* It consists of cells that have been hardened with keratin.
* Keratin is secreted by cells located in the deep layers of the epidermis called keratinocytes.
Stratum lucidum
- Thin somewhat translucent layer of cells (lying superficial to the stratum granulosum and under the stratum corneum)
- found especially in thickened parts of the epidermis (as of the palms or the soles of the feet)
Stratum granulosum
- Accumulate dense basophilic keratohyalin
- granules that contain lipids helping to form a waterproof barrier which prevents fluid loss from the body
- contains cells that have lost their nuclei.
- These cells remain active and secrete keratin.
- The cells contain granules in their cytoplasm that harbor keratin.
Stratum spinosum
- This layer mostly consists of keratinocytes held together by sticky proteins called desmosomes,
- helping make your skin flexible and strong
contains cells called prickle cells.
Keratin is synthesized in this layer.
Stratum basale
- Deepest of the epidermis,
- contains the only layer where the proliferation of skin cells can occur
- attaches epidermis to the dermis
contains epidermal stem cells.
cells can divide and move toward the surface pushing the old cells off of the superficial layers
This is the layer where basal cell cancer develops.
the body’s largest organ
skin
the epidermis
outermost, superficial layer
strata
The epidermis consists of stratified epithelium tissue arranged in layers
dermis
The deepest layer is the subcutaneous layer
dermis consists
consists of loose connective tissue and adipose tissue along with blood vessels and nerves
The epidermis consists of stratified squamous epithelium arranged in layers or strata. WHAT IS THE ORDER
Stratum corneum
Stratum lucidum
Stratum granulosum
Stratum spinosum
Stratum basale
CAN LUCY GET SOME BASALE
basement membrane
The epidermis is anchored to the dermis by
The epidermis does not contain
any blood vessels
The cells of the stratum basale are nourished by
the blood vessels in the dermis
Process that stratum basale get new cells
These cells can divide and move toward the surface pushing the old cells off of the superficial layers
there are a good number of keratinocytes located
in the epidermis
an abnormality of keratinocytes
Psoriasis
Keratinocytes
abnormally divide rapidly and migrate from stratum basale to stratum corneum.
Many immature cells reach the stratum corneum producing flaky, silvery scales (mostly on knees, elbows and scalp).
The epidermis also responds to the environment.
Friction causes the formation of corns and calluses.
The color of the skin results from
the activity of the melanocytes, not the number.They respond to ultraviolet radiation by producing more melanin pigment which turns skin a darker color.
Melanocytes are located in
the deepest layer of the epidermis.
The hair and middle layer of the eye contain
melanocytes. A condition known as malignant melanoma can develop in melanocytes.
Vitamin D
(aka cholecalciferol) is synthesized when a precursor molecule absorbs ultraviolet radiation.
