Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

COT Part I > Lecture 11: Integument > Flashcards

Lecture 11: Integument Flashcards

1
Q

Integument layers

A

-Epidermis (epithelium)
-Dermis; papillary + reticular (connective tissue)
-Hypodermis

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

Periderm

A

Unilaminar embryonic integument. Specialized to interact with amniotic fluid and protect the epidermis developing basal to it.

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

Papillary dermis

A

More cellular, loose CT. Smaller dermis layer closer to the epidermis

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

Reticular dermis

A

More fibrous, dense irregular CT. Significantly larger than papillary dermis.

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

Dermal papillae

A

Small bumps that extend from the dermis and invaginate the epidermis. Interrupted by interpapillary pegs (rete). Increases mechanical strength of layers.

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

Capillary plexus

A

Comprised of deep (lower) and shallow (upper) sections within the dermis. Blood supply for epidermis. Shunting blood to/from the shallow plexus helps in temperature regulation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Functions of the integument

A

-Structure
-Immune barrier/surveillance
-Fluid retention
-Vitamin D production

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

Keratinocytes

A

Primary epidermis cell. Produces keratins. SCs located in stratum basale. Connected by desmosomes.

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

Epidermis layers

A

Basal to apical:
-Stratum basale
-Stratum spinosum
-Stratum granulosum (LM visible in thick skin only)
-Stratum lucidum (LM visible in thick skin only)
-Stratum corneum

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

Stratum basale

A

Basal layer of epidermis. Contains keratinocyte stem cells and melanocytes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Stratum spinosum

A

Contains daughter cells from basal stem cells through asymmetric vertical division.

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

Stratum granulosum

A

Contains cells with visible keratohyalin granules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Stratum lucidum

A

0-2 cells thick, contains dying cells that still retain their cytoplasm.

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

Stratum corneum

A

Composed of keratin sheets bound by lipids and keratohyalin; originally contained in lamellar bodies of cells. Fillagrin precursor becomes a glue for keratin sheets that cells release as they die. Forms an H2O barrier.

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

Minor epidermis cell types

A
  1. Melanocytes
  2. Langerhans cells
  3. Merkel cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Melanocytes

A

Produce melanin and export to surrounding keratinocytes via cytocrine secretion of melanosomes. Primarily responsible for skin color and respond to UV radiation.

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

Langerhans cells

A

Resident dendritic APCs of the integument.

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

Merkel cells

A

Serve some role in interfacing with the nervous system and in mechanosensation.

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

Nervous elements of the dermis

A

-Meissner’s corpuscles
-Pacinian corpuscles
-Free nerve endings
-Ruffini endings
-Krause corpuscles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Meissner’s corpuscles

A

Located in papillary dermis. Sense touch.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Pacinian corpuscles

A

Located in deep dermis/hypodermis. Sense pressure.

22
Q

Hypodermis

A

Deep, adipose tissue-rich layer of integument.

23
Q

Free nerve endings

A

Located in dermis and epidermis. Can associate with hair follicles sensing hair deflections. Also sense pain and temperature.

24
Q

Ruffini endings

A

Located in dermis. Sense sustained pressure.

25
Q

Krause corpuscles

A

Located in dermis. Sense light touch and low frequency vibrations.

26
Q

Eccrine sweat glands

A

Coiled tubular serous glands that traverse the epidermis. Ducts are stratified cuboidal.

27
Q

Apocrine sweat glands

A

Large tubular serous glands. Found only in a few places, e.g. axilla. Typically secrete into hair follicles.

28
Q

Hair follicle structure

A

Invagination of the epidermis. Center hair shaft supported by inner and outer root sheaths (IRS, ORS)

29
Q

Inner root sheath

A

IRS is dominant to the follicle base and surrounds newly formed hair.

30
Q

Inner root sheath layers

A
  1. Cuticle
  2. Huxley’s layer
  3. Henle’s layer
31
Q

Outer root sheath

A

Dominant to the follicle apex, continuous with the epidermis.

32
Q

Hair bulb

A

Base of hair follicle from which hair shaft grows. Includes dermal papilla of hair and hair matrix

33
Q

Dermal papilla of hair

A

Connective tissue which organizes follicle development.

34
Q

Hair matrix

A

Epithelial region within follicle base which grows the hair shaft.

35
Q

Glassy membrane

A

Thick basement membrane continuous with epidermal basement; separates the follicle epithelium from CT parts. Facilitates the relative motion of hair as it grows.

36
Q

Radial layers of the hair shaft

A

Deep to outer:
1. Medulla
2. Cortex
3. Cuticle

37
Q

Hair growth phases and duration (in scalp)

A
  1. Anagen (2-3 years)
  2. Catagen (2-3 weeks)
  3. Telogen (2-3 months)
38
Q

Anagen

A

IRS elongates and pushes the hair bulb deeper into the dermis/hypodermis

39
Q

Catagen

A

Apoptotic regression of follicular epithelium, pulling the hair bulb back to the epidermis which forces the hair shaft out.

40
Q

Telogen

A

Resting phase throughout which the hair shaft is shed. Dermal papilla of hair and bulge region must be in close contact to re-enter anagen.

41
Q

Bulge region of hair

A

Small bulge in hair follicle where stem cells are found. Associates with arrector pili muscle.

42
Q

Arrector pili muscle

A

Attaches to follicle at the bulge; innervated by sympathetic nerve fibers to raise hair shaft erect.

43
Q

Types of burns

A

1st degree: epidermis
2nd degree: epidermis + superficial dermis
3rd degree: epidermis + deep dermis (nerve endings destroyed)
4th degree: epidermis, dermis, underlying bones/muscles/tendons (nerve endings destroyed)

44
Q

Raynaud’s phenomenon

A

AKA Renault’s disease. Loss of blood flow/sensation to the extremities. Defect in arteriovenous anastamosis control.

45
Q

Stratum corneum brick and mortar model

A

S. granulosum cells fill with lamellar bodies/granules with lipids, as well as other structural lattice proteins and keratin filaments bundled by filaggrin. Upon apoptosis, vesicles (mortar) are released to fill spaces between dead keratinocytes (bricks).

46
Q

Stratum corneum protein-lipid barrier molecular components

A

Outer lipid barrier with involucrin structural proteins. Inner tonofilaments bound by filaggrin, loricrin, and small Pro-rich proteins.

47
Q

Epidermal protective functions

A

Barrier to water, macromolecules/ions/toxins (except small moderately lipophilic substances), radiation (melanin), pathogens (antimicrobial peptides)

48
Q

Tanning process

A
  1. Photo-oxidation of melanin
  2. Redistribution of melanin granules to upper layers
  3. Increased # of melanin granules in skin -> color
49
Q

Keratinocyte vitamin D production

A

UV light cleaves 7-dehydrocholestrol into pre-vitamin D3 in epidermis; later transported from dermis by blood to liver then kidney and converted into active vitamin D.

50
Q

Vitamin D effects

A

Stimulates Ca absorption by GI, Ca reabsorption by kidney, bone resorption by Ocls

51
Q

Integument body temperature regulation mechanisms

A
  1. Activation of eccrine sweat glands
  2. Vasodilation of cutaneous blood vessels
  3. Arteriovenous anastamosis
52
Q

Arteriovenous anastamosis mechanism

A

Closure of AVA directs more blood toward the upper horizontal plexus, closer to the skin. Results in increased heat lost through radiation.

COT Part I (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions