Normal Skin Structure & Function I and II Flashcards
What features of the skin provide resistance to abrasion?
- keratinocytes
- desmosomes
- keratin filaments
- dermal CT
What features of the skin provide resistance to infection?
- keratinocytes
- Langerhans cells
- WBCs in dermis
What features of the skin provide prevention of dehydration?
- keratinocytes
- stratum granulosum
- lamellar bodies
What features of the skin provide protection of underlying tissue from UV light?
- keratinocytes
- melanocytes
What features of the skin provide synthesis of vitamin D?
keratinocytes
What features of the skin provide thermoregulation?
- sweat glands & hair
- dermal blood vessel distribution and regulation
What features of the skin provide excretion?
sweat glands
What features of the skin provide sensation of temperature, pressure, pain?
- sense organs including hot and cool receptors?
- Meissner’s corpuscles and Pacinian corpuscles (will be covered in neuro)
What two kinds of skin are recognized histologically?
- thick skin
- thin skin
Where is thick skin found?
- palms of the hands
- soles of the feet
Where is thin skin found?
everywhere besides palms of the hands and soles of the feet
What are the main cells found in the epidermis?
- keratinocytes
- melanocytes
- Langerhans cells
What type of epithelium makes up the epidermis?
stratified squamous epithelium
The keratin of keratinocytes are particularly rich in which three amino acids?
- cysteine
- lysine
- histidine
*amino acids involved in forming crosslinks within and between protein chains
Keratin filaments connect at the plasma membrane to what structure that attaches adjacent keratinocytes?
desmosomes
Keratin filaments connect at the plasma membrane to what structure that attaches keratinocytes to the basal lamina?
hemidesmosomes
The stratified squamous epithelium of the skin is composed of what 5 recognizable layers (sometimes 4)?
- basal layer (stratum basale, stratum germinativum)
- spinous layer (stratum spinosum)
- granular layer (stratum granulosum)
- clear layer (stratum lucidum) - found in thick skin
- cornified layer (stratum corneum)
The youngest keratinocytes are found in which layer of the skin?
basal layer (stratum basale, stratum germinativum)
The youngest keratinocytes, found in the basal layer, are what type of cells?
cuboidal or columnar
Hemidesmosomes are the target of immune destruction in which autoimmune disease?
bullous pemphigoid
Desmosomes are the target of immune destruction in which autoimmune disease?
pemphigus vulgaris
What do basal keratinocytes secrete?
Type VII collagen
Type VII collagen is important for what?
Type VII collagen is the main component of anchoring fibrils which reinforce the connection of epidermal basal lamina with underlying dermis
What type of collagen underlies several kinds of epidermolysis bullosa (a family of genetic blistering diseases)
Type VII collage