Skin and subcutaneous tissue (dave's notes) Flashcards
Define epidermis
The epithelium of the skin, stratified squamous keratinising variety
What is the uppermost layer of epidermis made of? What depends on this layer?
Dead cells, composed largely of keratin. Skin thickness is dependent on this layer.
What determines skin colour?
Activity (not number) of melanocytes
Where is melanin taken up?
By cells adjacent to melanocytes
What is the embryological origin of connective tissue?
Mesoderm
How is skin bound to underlying structures? What is the effect of this?
Bound by areolar tissue to underlying structures to a variable extent which has functional benefits.
What to flexure lines indicate?
The site of flexure lines does not always correspond to the topography of the underlying structures.
How many sweat glands to we have?
3 million
What types of sweat glands do we have?
Eccrine and apocrine
What do eccrine glands secrete?
Water
How do apocrine glands differ from eccrine glands? Where are apocrine glands found?
Larger than eccrine, open into hair follicles, found in axillae, areolae, breasts.
Where are sebaceous glands found? Describe them.
Located in hairy skin, a grape like structure beside the hair follicle.
What is hair? What is special about its growth?
Hard keratin from hair matrix. Phasic growth.
What muscles are associated with hair? What do they connect to? What is their innervation?
Erector pili muscles. These attach to connective tissue. Sympathetic innervation.
What is another tissue that grows in a similar way to hair?
Nails
