ToB - skin Flashcards
functions of the skin
barrier
sensation
thermoregulation
sociosexual communication
what are the different layers of the skin?
stratum corneum
stratum granulosum
prickle cell layer (stratum spinosum)
stratum basale
how does keratinocyte differentiate in the different layers of the skin?
- basal layer: keratinocyte mitosis
- prickle cell layer - loose ability to divide & produce KERATINS
- granular layer - loose plasma membrane and start to become corneocytes, contains keratins & enzymes
- stratum corneum - dead flattened corneocytes
what are the structures within the skin?
fibroblasts blood vessels lymphatics mast cells nerves collagen, elastin & ground substance papillary layer anchors epidermis erector pilli muscles
what is the dermo-epidermal junction?
basement membrane
dermal papillae
what is melanocytes
dendritic
occur at intervals of BASAL layer of epidermis
produce melanin (more in darker skin tone)
number does not change in skin colour
difficult to see
what are langerhans cells?
dendritic cells of BM origin scattered in prickle layer difficult to see present antigents to T cells mediate immune reaction - contact with skin
what is virtiligo?
autoimmune destruction of melanocytes
what is psoriasis?
thickening of prickle cell layer
inflammation
hyperproliferation
what is malignant melanoma?
primary cause UV
mutations in melanocytes
prognosis linked to basement membrane
surgery
what is the macroscopic structure of skin
varies with site, sex, age, ethnicity and exogenous influence
colour
hair
laxity / wrinkling
using examples, how do disease influence the macroscopic structure of disease?
UV abnormalities - UV damages collagen & elastin
alopecia areata - women
skin cancers e.g. basal cell carcinoma (BCC) or malignant melanoma - both rare with black skin
