Skin Structure and Function 1 Flashcards
What are the 5 components of skin in mammals?
Epidermis Dermo-epidermal junction Dermis Sub-cutis Appendages
What layer of the skin makes up the epithelium?
Epidermis
What type of epithelium is the epidermis?
Stratified squamous epithelium
Is the epidermis or dermis more cellular?
Epidermis
What of the 4 basic tissue types is the dermis?
Connective tissue
What is the sub-cutis mainly composed of?
Fat
What are the 4 skin appendages?
Nails
Hair
Glands
Mucosae
What type of epithelium lines the blood vessels?
Simple squamous epithelium
Where is glandular epithelium found in the skin?
In sweat and sebaceous glands
What is the periderm?
When does this generally disappear?
Outer layer of the bilaminar foetal epidermis
Before birth
What does the epidermis form from in the embryo?
Ectoderm cells form a single layer of periderm
There is a gradual increase in layers of cells before the periderm is cast off
What is the ectoderm?
One of 3 primary germ layers in the very early embryo
What is the embryonic origin of the dermis?
Mesoderm
What is the neural crest?
A temporary group of cells unique to vertebrates that arise from the embryonic ectoderm cell layer and in turn give rise to a diverse cell lineage
What is the embryonic origin of melanocytes?
Neural crest
At 4 weeks, what layers is the skin made up of? (3)
Periderm
Basal layer
Dermis (corium)
At 16 weeks, what layers is the skin made up of? (5)
Keratin Layer Granular layer Prickle ell Layer Basal Layer Dermis
At how many weeks is the skin fully formed with appendages?
26 weeks