Chapter 11.10 - Integumentary System Flashcards
Skin is composed of what two layers?
epidermis and dermis (not including hypodermis)
___ is the most superficial layer of the skin
epidermis
The epidermis is ___ and ___
thin; avascular
How does the epidermis receive oxygen and nutrients?
via diffusion from neighboring cells
What kind of cells is epidermis made of?
stratified squamous cells
What do stratified squamous cells look like?
flattened, disk-shaped cells arranged into multiple layers (4-5 layers of keratinocytes)
Layers of epidermis from superficial to deep
stratum corneum, stratum lucidum, stratum granulosum, stratum spinosum, stratum basale
Where is stratum lucidum present?
only in the palms of the hands and the soles of the feet
Stratum corneum is composed of:
dead, fully differentiated keratinocytes (corneocytes)
Stratum corneum function
provides protection against infection, dehydration, physical harm
Stratum lucidum is composed of:
dead keratinocytes that have not yet fully differentiated to corneocytes
Stratum granulosum composed of:
keratinocytes
What does Stratum granulosum secrete?
lamellar bodies (helps form hydrophobic membrane to create water barrier)
Function of stratum spinosum
provides skin with strength and flexibility via desmosomes
Which layer of the epidermis contains the highest amount of Langerhans cells?
Stratum spinosum (they are present in all layers but most prevalent in spinosum)
Langerhans cells are:
dendritic cells of the epidermis
Stratum basale is separated from the dermis by the:
basement membrane (basal lamina)
How does the stratum basale attach to the basement membrane?
via hemidesmosomes
stratum basale provides continuous renewal of:
epidermal keratinocytes
stratum basale houses specialized cell types like:
melanocytes; merkel cells