EXAM2_L16_17_Integument Flashcards

1
Q

What are the 5 derivatives of Epidermis? Where derived from?

A

Surface Ectoderm

  1. Hair follicles,
  2. Sebaceous glands
  3. Sweat (sudoriferous) glands
  4. Nails
  5. mammary glands
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is hypodermis? is it part of integument?

A

Subcutaneous fascia- not part of integument

Integument is EPIDERMIS and DERMIS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Integument- 2 parts and defining layers

A

Epidermis- above papillary layer (BSGLC)
Dermis- between subcutaneous & Epidermis
-Contains reticular layer (glands/ducts/vessels)
and papillary layer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What type of epithelium for Epidermis and dermis?

A

Epidermis- keratinized stratified squamous ECs

Dermis- LCT, DiRCT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Dermal papillae vs epidermal rete ridges

A

Dermal papillae- dermis ridges protruding into epidermis

epidermal rete ridges- epidermis protruding into dermis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

5 Layers of integument? What cells in each layer?

A
  1. Basale
  2. Spinosum (melanocytes, dendritic cells, keratinocyte)
  3. Granulosum
  4. Lucidum
  5. Corneum
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Basale- Name- Structure- 3 Function- dysfunction?

A

germinativum
-single cell layer-cuboidal/low columnar/
-vitD production-Stemcells- desmosomes/hemidesmosomes
PSORIASIS- rapid proliferation of cells ~7days vs 50

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Spinosum

A

Prickle cell layer
cuboidal to squamous
-vitD- mitotically inactive-cytoplasmic spines-
DESMOSOMES-(NODES OF BIZZOZERO)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Granulosum- thickness? observation? important structural component?

A

1-3 layers- squamous cell
Still retain nuclei
Keratohyalin granules (keratinization)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Corneum

A
squamous- variable thickness
no nucleus
keratinized cells (soft keratin)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Papillary Layer- composition? Where at?

A

Dermis- between basale and reticular layer
-LCT (more cellular than reticular layer)
-thin collagen fibers I and III
Thin elastic fibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Reticular Layer- Composition? Where at?

A

Dermis- under papillary layer

  • DiRCT- Thick Collagen Type I fibers- Thick Elastic Fibers
  • Less cellular
  • closely packed fiber bundles
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

EVG Stain- what highlighted? Color?

Weigert elastic stain?

A

Collagen fibers- Red
Elastic fibers- Black
WES-Highlights elastic and collagen fibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Langer’s Lines

A

collagen & elastic fibers orient in parallel lines

surgeons use these lines for faster wound healing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Wound healing- 4 things

A

Stratum basale ramps up mitosis

  1. -migration of proliferating cells
  2. -exfoliation of dead keratinocytes frees scab
  3. -fibroblasts differentiate into myofibroblasts (directed by TGF-B1)
  4. -Myofibroblasts involved in wound closure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

2 functions of Keratinocytes?

Where are they located and why?

A

-Flaggrin & Int. Filaments (keratin filaments-tonofilaments)
1. KG’s aggregate tonofilaments into tonofibrils by releasing Flaggrin
2. Water barrier-Lamellar bodies exocytosis pro-barrier lipids,enzymes,proteases into ICS between granulosum/corneum
Keratinocytes located at Basale b/c bound by hemidesmosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Nodes of Bizzozero

A

Desmosomes connecting cytoplasm of keratinocytes

called Bizzozero AT LM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Desquamation

A

Exfoliation-

-result of proteolytic degradation of desmosomes in a pH dependent manner

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Melanocytes- Derived from? Migrate from?to? What drives? What function? what don’t they have? transport?

REMEMBER THEY LOOK LIKE AN UPSIDE DOWN ORANGE OCTOPUS IN THE PICTURE

A
  • Neural Crest
  • migrate to stratum basale
  • PAX3 of dermis drives differentiation
  • No desmosomes
  • Produces melanin granules
  • Transport kinesin/dynein
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How do MELANIN granules end up in keratinocytes? what determines integument pigmentation?

A
  • keratinocytes phagocytose melanocyte processes to take up melanin granules
  • Pigmentation determined by rate of melanin degredation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

3 epidermal cancers. ABCD rule

What is happening to keratinocytes?

A
  1. Basal cell carcinoma
  2. Squamous cell
  3. malignant melanoma
    ABCD: asymetrical shape, border irregular, color variation, diameter >6mm
    Keratinocytes migrating into the Stratum Spinosum layer
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Langerhan’s cells: Function? What kind of cell? where migrate from? 3 structural characteristics?

A
  • Immunocytochemistry CD1a
  • APC’s (present to T-lymphocytes)
  • migrate from marrow to spinosum
    1. indented nucleus-
    2. no desmosomes-migratory
    3. rod-shaped BIRBECK GRANULES in cytoplasm
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Langerhans cells- Lectin Langerin- Birbeck granules-HIV-1

WHAT IS THIS SHIZ?

A

Langerhans cells express lectin Langerin

  • induces formation of Birbeck granules
  • BG’s internalize and degrade HIV-1
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Merkel’s Cells- Where derived?- Found in what layer? in what part of body? 2 Structure details? 2 Functional details? What stain used?
Merkel cell carcinoma- rare but agressive- Sun exposure like BCC

A
Ectoderm derived
-in stratum basale
-in fingertips
-dense-cored neurosecretory granules
-desmosomes tether MC's to keratinocytes
-synapse w/ pseudounipolar neurons
-tactile sensation
Toluidine blue stain- appear lighter in color/large round nucleus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What 4 cells of epidermis?

A
  1. Keratinocytes (
  2. Melanocytes (Neural Crest)
  3. Langerhan’s (marrow->spinosum) APC’s
  4. Merkel’s (ectoderm)
26
Q

Innervation of Integument 5 types. What structural characteristic of corpuscles?

A
  1. Free nerve endings (pain, temp, tactile)
  2. Pacinian corp. (deep pressure, vibration)-ret lam.
  3. Meissners corps (light touch. tactile)-derm pap.
  4. Merkel’s cells (tactile)
  5. Ruffini’s corps (tactile)
    Corpuscles have CT encapsulated nerve endings
27
Q

Hair Follicle 6 parts

Note: outside GM is dermis- inside is epithelium

A
  1. Hair (medulla/cortex/cuticle)
  2. IRS- int root sheath
  3. ERS-ext root sheath
  4. GM (glassy membrane=basal lamina)
  5. CT
  6. HP- hair papilla enclosed by hair bulb
28
Q

Cortex, cuticle , hair cells (what type of cells in each)?

A

Cortex- cuboidal
cuticle - squamous cells
hair cells- hard keratin
color determined by melanin content and typej

29
Q

Stroma & Parenchyma

A

Stroma- supporting cells

Parenchyma-functional cells of the organ

30
Q

APOCRINE

-Gland type? Example?

A

-released from apical part of cell into DUCT
-Released with some Cytoplasm and PM
ie- lactating mammary gland
-COMPOUND TUBULOACINAR
think of boobs- complicated ductwork system

31
Q

HOLOCRINE

Gland type? Example?

A

-Cell debris release into duct after apoptosis
ie- sebaceous glands of integument
BRANCHED ACINAR

32
Q

MEROCRINE

A

Exocytosis from apical end into duct
ie- sweat glands of integument
SIMPLE COILED TUBULAR

33
Q

Type of secretion for each?
Compound tubuloacinar
Simple Branched Acinar
Simple coiled Tubular

A

CTA-Apocrine (mucus/serous- mammary-submandibular)
SBA- Holocrine- mucus into lumen (stomach)
SCT- Merocrine- eccrine sweat (deep in dermis)

34
Q

Sebaceous Glands- derived from? classification of gland? Type of secretion? What secreted? Where located?

A
  • derived from epidermis
  • branched acinar
  • holocrine secretion of sebum (lipid + cell debris) after apoptosis.
  • located right next to hair shaft
35
Q

Sweat glands- 2 types. 2 similarities?

A

Derived from epidermis
-Simple coiled tubular
-Merocrine
Eccrine- ACh/Small Lumen/Sweat,ABiotic glycoproteins
Apocrine-Norepinep/protein-rich stored in lumen-BIG Lumen

36
Q

Eccrine Sweat Glands-
3 similar things to apocrine
4 things different: Innervation? product? structure?

A
  • derived from epidermis
  • Simple coiled tubular
  • Merocrine
    1. -stimulated by Sympathetic ACh
    2. -Sweat & antibacterial glycoprotein granules
    3. -Narrow lumen in duct
    4. Three cell types
37
Q

Apocrine Sweat Glands-
3 similar things to eccrine
5 things different: where? cell types? Innervation? product? structure?

A
  • derived from epidermis
  • Simple coiled tubular
  • Merocrine
    1. Hair follicles of Axilla, Anus, External Genitals
    2. One cell type
    3. Innervation by sympathetic Norepinephrine
    4. Protein-rich secretion can be stored in lumen
    5. WIDE lumen
38
Q

Cell Composition of Eccrine Sweat Glands. 3 type of cells & respective compositions

A
  1. Clear Cells (columnar, produce sweat, mitochondria, glycogen, increased surface are of PM, adjacent to intercellular canaliculi)
  2. Dark Cells (pyramid, antibacterial glycoprotein granules, RER, Golgi, adjacent to lumen)
  3. Myoepithelial cells (contraction to assist secretion)
39
Q

Nail structures-

A
Free edge
Nail groove
Nail fold (hang nail)
Lunula
Nail body
Eponychium (cuticle)
40
Q

What part of the nail is epidermal germinative zone? What is hyponychium?

A

Nail matrix- Located close to the epinychium(cuticle) under the nail root
Hyponychium thick epidermis attaches free edge of the nail

41
Q

Where is Epidermis derived from?

Where is the DERMIS derived from?

A

Epidermis-ECTODERM

Dermis- MESENCHYME from:

  1. Lateral plate mesoderm (limbs/body wall)
  2. Paraxial mesoderm (back)
  3. Neural crest (face and neck)
42
Q

What induces ectoderm to form the epidermis?

A

BMP4 and FGF

43
Q

What allows ectoderm to form the neural plate?

Describe the BMP4 concentration gradient and why its important

A

Noggin, Chordin, Follistatin are expressed by the notochord and inhibits BMP4.

Low BMP4 induces neural plate
Intermediate BMP4 induces neural crest
High BMP4 induces epidermis

The concentration of BMP4 is low in the middle and increases laterally to the outside so that each layer develops correctly.

44
Q

What two proteins induce sclerotome development?
What protein induces dermatome development?
What induces myotome development?
What does each paraxial layer secrete respectively?

A

Sclerotome-SSH & Noggin&raquo_space;»[PAX1]
Dermatome- NT-3 &raquo_space;»> [PAX3]
Myotome- WNT &raquo_space;»> [MyoD/Myf5]

45
Q

SSH,PAX,WNT,NT

A

SSH-Sonic hedgehog - sclerotome>PAX1
PAX- Paired box genes- dermis
WNT- Wingless-type genes- myotome>MYF5/MyoD
NT-neurotrophin genes- dermatome>PAX3

46
Q

Lines of Blaschko

A

1901 derm disorders saw the segmentation lines

47
Q

What holds all the cells of the epidermis together?

A

desmosomes and hemidesmosomes. They change and are lost by change in pH.

48
Q

Why don’t melanocytes have desmosomes?

A

They migrate- keep moving through cells- at basale level

49
Q

melanosomes -

A

Kinesin transport melanin granules “melanosomes” along cytoplasmic processes of melanocyte until it makes contact with a keratinocyte. Keratinocyte phagocytose melanocyte processes in order to take up the melanin granules.
the granules then transported away from keratinocyte interior by dynein.

50
Q

Cells in the stratum basale
Cells in the stratum spinosum
cells in the stratum granulosum

A

Basal- keratinocytes, melanocytes
spinosum- merkel cells, langerhans
granulosum-

51
Q

If you have a problem with ACH release or cholinergic response:
if you have problem with NE or adrenergic response?

A

produce too much sweat or not enough sweat

Produce too much sweat or not enough

52
Q

If you have someone who stinks really bad when they sweat what gland can you associate it with?

A

Apocrine- high protein stored in lumen- bacteria
-large protein in lumen- PUBES - NE-
Develop during PUBERTY

  • Eccrine doesn’t smell b/c it has antibacterial glycoprotein granules
  • small antibacterial lumen-ACH-3celltypes-merocrine-coiled tubular
53
Q

3 cells of eccrine sweat glands

A

Clear- make sweat->intercellular canaliculi>small lumen
(increased mitochondria/glycogen)
Dark- make antibac glycoprotein granules close to lumen
(increased RER/golgi)
Myoepithelial- contract for secretion

54
Q

What embryological structure inhibits BMP4? what does it release? why important? what is the gradient?

A

Notochord releases noggin, chordin, follistatin inhibiting BMP4 close toward center
-established gradient has low center BMP4 and increasing BMP4 away from center
Important because bmp4 induces development of structures based on concentration.
Low BMP4- neural plate
Med- Neural crest
High- Epidermis

55
Q

what layer of epidermis would you see nodes of blizzazaro?

A

stratum spinosum

56
Q

Where do you find bipolar neurons? 3 places

A

Nasal cavity
Inner ear
Retina

57
Q

3 types of cancer of skin, frequency, seriousness

A

Basal Cell- most common
Squamous cell- 2nd most common
Malignant melanoma- not as common- Most serious

58
Q

PSORIASIS

A

Normal travel time 50-60 days

rapid proliferation is about 7 days in psoriasis

59
Q

Where vitD production?

Where mitotically active?

A

vitD- basale-spinosum

mitosis-basale

60
Q

Stratum granulosum

A

1-3 cell layers thick
Have nuclei
Squamous
Keratinophyalin granules give it the grainy look

61
Q

Intermediate filament associated proteins- where are they? how do they work? what do they do? How do you identify them on TEM?

A

Filaggrin proteins inside Keratohyaline granules- Cause keratin tonofilaments to aggregate into tonofibrils

look like black tadpoles starting to form black fiber tails

62
Q

What creates the water barrier of the epidermis?

A

Lamellar bodies next to plasma membranes secrete (exocytosis) into space between Granulosum and corneum
to create a barrier

granulosum cells secrete the lamellar bodies and the membrane is setup just deep to the corneum layer

pro-barrier lipids-lipid enzymes and proteases