Structure and Function 1 Flashcards
How many GP consultations for skin?
I in 5
Which germ layer is the epidermis made from?
Ectoerm cells form single layer periderm
Gradual increase in layers of cells
Periderm cells cast off
Which germ layer forms the dermis?
The dermis is formed from the MESODERM (below ectoderm)
KGPBD
Keratin layer Granular layer Prickle cell layer Basal layer Dermis
Connective tissue, less cellular
Dermis
What is the sub-cutis mainly made from
Fat
The epidermis is 95% made from these cells
Keratinocytes
Epidermis is made of which type of cells?
Stratified squamous
How many layers in epidermis?
4
KGPB
Other cells found in the epidermis
Melanocytes
Langerhans cells
Merkel cells
Where do keratinocytes migrate from and what does this mean for the epidermis
Migrate from the basement membrane
Continous regeneration of epidermis
28 days from bottom to top
How many cells thick is the basal layer?
1 cell
Small cuboidal
Usually one cell thick
Small cuboidal
Lots of intermediate filaments (keratin)
Highly metabolically active
Basal layer
Lots of intermediate filaments in this layer
Basal layer
Larger polyhedral cells
Lots of desmosomes (connections)
Intermediate filaments connect to desmosomes
Prickle cell layer
2-3 layers of flatter cells Large keratohyalin granules – contain structural filaggrin & involucrin proteins Odland bodies (lamellar bodies) High lipid content Origin of “cornified envelope” Cell nuclei lost
Granular layer
Which layer are nuclei lost in?
Granular layer
Which layer are odland bodies found?
Granular
Which layer are lamellar bodies found in?
Granular
lamellar bodies = odland bodies
Origin of “cornified envelope”
Granular layer
Layer with a high lipid content?
Granular layer
Where are corneocytes found?
Keratin layer
What are corneocytes?
Overlapping non-nucleated cell remnants
Where is the insoluble cornified envelope?
Keratin layer
