The skin is composed of two district layers. Name them.
Epidermis
Dermis
What is the outermost layer of the skin?
Epidermis
What is another name for the hypodermis?
superficial fascia
What is the only layer of skin that is vascularized?
Dermis
Because of its _____ composition, the hypodermis also acts as a ______ and an _______ that reduces heat loss.
Fatty
Shock Absorber
Insulator
What layer of the skin makes up the bulk?
Dermis
Name the cells populating the epidermis
Keratinocytes
Melanocytes
Dendritic cells
Tactile cells
What fiber gives the epidermis its protective properties?
Keratin
What cells make up keratin in the epidermis? What layer of the epidermis do they originate from?
Keratinocytes
Stratum Basale
Most epidermal cells are . . .
Keratinocytes
Keratinocytes are tightly connected by . . .
Desmosomes
Which cells undergo almost continuous mitosis in response to promoting by epidermis growth factor, a peptide produced by various cells throughtout the body
Keratinocytes
Persistent friction causes a thickening of the epidermis called a . . .
Callus
How are melanocytes described?
Spider-shaped epithelial cells that synthesis the pigment melanin
What pigment does melanocytes synthesis?
Melanin
Melanin accumulates in membrane-bound granules called . . . that motor proteins move along actinfilaments to the end of the melanocytes's process
Melanosomes
What is the function of melanosomes?
Motor proteins move along actinfilaments to the end of the melanocyte's process
The melanosomes accumate on the superficial, or "sunny side" of the keratinocytes nucleus, forming . . .
A pigment shield that protects the nucleus from the damaging effects of ultraviolet radiation in sunlight
What are star-shaped cells that arise from bone marrow and migrate to the epidermis?
Dendritic Cells
Langerhans cells are another name for what cell epidermal cell?
Dendritic cells
What is the function of Dendritic cells?
To ingest foreign substances
Key activators of our immune system
Merkel cells are another name for what epidermal cell?
Tactile cells
Describe tactile(Merkel) cells?
Spiky hemisphere
What are tactile(Merkel)cells' function?
They function as sensory cell receptors for touch. Each tactile cell is intermittently associated with a disc-like sensory nerve ending.
Where can you find thick skin?
Palms
Soles of the feet
Fingertips
Name the 4(5 if thick skin) layers of the epidermis. Deep to superficial.
Stratum basale
Stratum Spinosum
Stratum Granulosum
(Stratum Lucidum[only for thick skin])
Stratum Corneum
In thin skin, which covers most of the body, the _______layer appears to be absent and other strata are _______.