integument REMAKE Flashcards
what are the 2 layers of the integumentary system
what is not a layer ?
- dermis
- epidermis
- hypodermis is NOT a layer
what are the 5 layers of the epidermis
Come Lets Get Sun Burn
- stratum corneum
- stratum lucdium
- Stratum granulosum
- Stratum Spinosum
- Stratum basale
what are the charecteristics of the stratum corneum
What does it protect against?
(3)
- it is the most superficial layer
- 20-30 layers of dead anucleated keratinocytes
- protects against friction and water loss
- what are the characteristics of the stratum lucdium (2)
- 2-3 layers of dead anucleate cells
- only in thick skin
what are the characteristics of stratum granulosom
- 3-5 layers of keratinocytes with distinct
- distinct kerato-hyaline granules
what are the characteristics of stratum spinosum
- several layers of keratinocytes joined by desmosomes
- langerhan cells are present
what are the characteristics of the stratum basale (5)
- deepest layer
- single layer of if cuboidal - low columnar cells
- in contact with the basement membrane
- mitosis occurs here to create new skin cells
- ## melanocytes and merkel cells are present
what is the basal layer also called what is a special characteristic about this layer
- stratum germanitivum
- only layer that has dividing cells
what type of cells make up the epidermis
- keratinized stratified squamous epithelium
what layer of the epidermis are hemi - desmosomes closely associated with
- basal layer
what is the difference between thick and thin skin
- thick - has no hair, no errector pilli, no sebaecous glands
- thin - no stratum lucidum
what is the origin of the epidermis
surface ectoderm
what is the origin of merkel cells and melanocytes
neural crest
what is the origin of langerhan cells and what are their function
- monocytic origin ,
- macrophages of the epidermis ( immune system)
what do merkel cells do?
light touch sensation
what is the function of melanocytes
produce melanin to protect the dna in the nucleus from UV damage
what is the function of the meisner corpuscle?
light touch and highly sensitive to sensation caused by low frequency vibrations
- tactile receptors