Structure and function

Question 1

3 layers

Answer 1

Epidermis, Dermis, Subcutaneous fat (panniculus)

Epidermis- comp of keratinocytes cov by keratin, the stratum corneum.

Question 2

Prinicipal component of dermis

Answer 2

Collagen

Question 3

measurement of epidermis in palms and soles and on the eyelid

Answer 3

1. 5mm

0. 1 mm- eyelid

Question 4

Dermis is thickest where?

Answer 4

Back. 30-40x thick.

Question 5

follicles and eccrine sweat units originate in what month of fetal life?

Answer 5

3rd.

Question 6

first few weeks of fetal life, has non ker cuboidal cells called…

Answer 6

periderm later replaced by multilayered epidermis

Question 7

Adult epidemis 3 basic cell types

Answer 7

keratinocytes, melanocytes, and langerhans cells

Question 8

Mutations in genes for keratin 5 and 14. assoc w

Keratin 1, 10 assoc w.

Answer 8

5,14- EBS epidemolysis bullosa simplex

1,10- epidemolytic hyperkeratosis

Question 9

epidemis :
innermost basal layer 
malphigian or prickle layer 
granular layer 
horny layer 

name each.

Answer 9

inner- Stratum germinativum
Mp- Stratum spinosum
gran- stratum granulosum
horny- st. corneum.

Question 10

Stem cells have high expression of what? and low what?

Answer 10

High B1 integrins

Low desmosomal proteins, desmoglein 3.

Question 11

Abnormal keratinization manif as

Answer 11

parakeratosis (retained nuclei), Corps ronds ( round, clear to pink abn ker cells), Grains (elongatedC basophilic, abn ker cells)

Question 12

oxidation injury to ker cytes can be prevented by

Answer 12

Vit c in the form of L ascorbic acid

Question 13

Apoptosis apeara in what stain

Answer 13

HE

Question 14

lamellar granules contribute to what function

Answer 14

skin cohesion.
Impermeability.

defect leads to ( Lamellar ichthyosis, flegel hyperkeratosis)

Question 15

Func of glycolip like ceramide

Answer 15

Water barrier

Question 16

Desmosomal adhesion depends on

Answer 16

cadherins, calcium del desmoleins, and desmocollins.

Question 17

profilaggrin is what?

Answer 17

Precursor to filaggrin. For keratin fil agg.
conv to filagrin occ in granular layer

Kallikrein related peptidase 5 for profilagrin cleavage.

Question 18

ichthyosis vulgaris has dimished what layer or absent what?

Answer 18

Granular layer.

cont to retention hyperkeratosis.

Question 19

what contributes to formation of soft flexible keratin?

Answer 19

Keratohyalin. hard without it.

Question 20

what are critical for cell migration.

Answer 20

claudin-1, occludin.

Question 21

on what week are melanocytes found on the fetal epidermis

Answer 21

8th week of devt

Question 22

Ratio of melanocyte to keratinocyte

Answer 22

1:10

Question 23

one melanocyte in contact w a great num of keratinocytes together are called.

Answer 23

epidermal melanin unit.

Question 24

shape of melanocytes in red head

Answer 24

rounder prod more pheomelanin.

mc1R impt in regaulation of melanin prod.

Question 25

eumelanin optimal at what ph

Answer 25

6.8

Question 26

langerhand found scattered where

Answer 26

among kerstinocytes of stratum spinosum.

comp 3-5% of this layer.

Question 27

langerhans stained w what?

Answer 27

Cd1alpha

S100 immunostain

Question 28

BMZ is comped of what 4 comp.

Answer 28

Plasma membrane of basal cells w the spec att plates (hemidesmosomes) and an electrolucent zome called lamina lucida, the lamina densa ( basa lamina) inc anchorinng fibrilsC dermal mucrofibrils and collaged fibers.

Question 29

major compo of basal lamina and of anchoring fibrils.

Answer 29

Type 4 collagen - basal lamina

Type 7- anch

Question 30

2 major hemidesmosomal proteins w what diseaaes.

Answer 30

BP230 (bullous pemphigoid ant 1) 
BP 180 ( bullous pem anti2, 17 collagen)

Question 31

Laminin 5 (lam 332) and coll 4 is a major component of what respectively.

Answer 31

5- Lamina lucida, lamina densa

4- lamina densa

Question 32

what const skin adnexa

Answer 32

Eccrine and apocrine gladns, piloseb units.

Question 33

the intrepid spiral duct w opens directly to skin surface is called the

Answer 33

acrosyringium..

Question 34

apocrine units are outgrowths of

Answer 34

upper portion of hair follicle.

Question 35

stains what color in HE stain.

apocrine and eccrine

Answer 35

Apocrine- deeply red.

Ecrine- pale pink

Question 36

anagen hair lasts how many yrs.

Answer 36

3-5 yrs. 85-90% of scalp hair.
scalp anagen grow 0.37mm a day.

catagen / involution lasts 2 weeks.

Telogen, resting phase- 3-5 months.

Question 37

histo; catagen hairs are best identified w presence of what?

Answer 37

Apoptotic cells in the outer root sheath.

Question 38

shape of the scalp hair of white people

as well as the pubic, beard, eyelas.Black people

Answer 38

White- Round

the rest oval.

Question 39

pair the ff; Large / small melanosome to white and black people.

Answer 39

Large melanosome- Black people

Small- White

Question 40

Seb glands are most abundant where?

Answer 40

Face
scalp
except palms and soles

Question 41

fingernails grow ave of how many mm per day

Answer 41

0.1mm/day.
4-6 mo to replace complete naila.
12-18 mo for great toe nail.

Question 42

endogenous pigment follow contour of what? Exogenous pigments also.

Answer 42

end- LuNula

Ex- CUTicle

Question 43

what happens on the 6,12,24th week of fetal life in the dermis.

Answer 43

6- dermis is a pool of sxattered dendritic shaped cells.
12- fibroblasts are actively synthesizing reticulum fobers, elastic fibers and collagen.
24- fat cells beneath dermis.

Question 44

represents 70% of dry weight of skin

Answer 44

collagen rich in hydroxyproline, hydroxylysine and glycine

Question 45

Type __ collagen is the major comp of the dermis

Answer 45

Type 1 collagen

Question 46

Defects in collagen leads to what inheritable diaeasese

Defects in elastic tissue

Answer 46

Ehlers danlos syndrome
X linked cutis laxa
osteogenesis imperfecta

elastic: marfan
pseudoxanthoma elasticum.