Brainscape's Knowledge GenomeTM

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


See full index

Histo/Physio (14.5) > Skin and Glands > Flashcards

Skin and Glands Flashcards

1
Q

Layers of the epidermis

A 
Basale
Spinosum
Granulosum
Lucidum
Corneum
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Stratum Basale

A

Mitotically active cells that attach directly to the basement membrane by hemidesmosomes. Single layer of basophilic cuboidal or columnar cells.

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

Stratum Spinosum

A

Still mitotically active, but cells are starting to differentiate. Keratinocytes are connected to each other by desmosomes. Largest layer of epidermis.

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

Stratum Granulosum

A

Bundles of Keratin aggregates bound via accessory proteins like filagrin (keratohyalin granules)

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

Stratum Lucidum

A

Palms and soles of feet only. No nuclei or granules

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

Stratum Corneum

A

Non-nucleated dead cells filled with keratin.

As you go higher, fat and desmosome linkages disappear until “squames” start to sluff off

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

Thin vs. Thick skin

A

Size of Stratum Corneum

Thick skin DOES NOT have hair follicles (palms and soles)

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

What does Keratohyalin promote?

A

Within the SG layer, it promotes the dehydration of cells and cross-linking of keratin fibers

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

Layers of Dermis

A

Papillary Layer

Reticular Layer

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

Papillary Layer

A

Fine bundles of collagen. Loose connective tissue in this area that interdigitates with the epidermis for strong attachment. Mast cells, fibroblasts and leukocytes are present here

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

Reticular layer

A

Large bundles of collagen. Much thicker, dense irregular connective tissue with more fibers and fewer cells. Elastic fibers also present

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

Where are melanocytes?

A

Basal layer but they project to spinosum

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

Eumelanin vs. Pheomelanin

A
  1. Brown and Black melanin

2. Melanin for redheads

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

Cytology of melanocytes

A
  1. Many small mitochondria
  2. Short cisternae of RER
  3. Well developed golgi
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Steps of melanin synthesis

A
  1. Tyrosine synthesized in RER, processed in the golgi
  2. Tyrosine accumulates in the vesicles that also have a fine matrix of other proteins (Stage I melanosomes)
  3. Stage II melanosomes: Melanin synthesis begins
  4. Stage III - Deposited and accumulated melanin
  5. Stage IV - No tyrosinase left and melanosome is mature and full of melanin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Activity of Tyrosinase

A

Converts tyrosine to DOPA which is polymerized and transformed to melanin

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

Melanosomes after they bud off

A

Keratinocytes cleave melanosomes off of melanocytes, they go to nearby keratinocytes in the spiney layer and basal layer and go close to the nucleus to shield against UV radiation

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

Albinism vs Vittligo

A

Dysfunction in the melanocyte pathway or tyrosinase pathway causing hypopigmentation. Related to vitiligo where you lose pigmentation due to melanocyte deterioration (depigmentation)

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

Merkel Cells

A

Slowly adapting somatosensory cells that are found in the SB.

Allow for light touch discrimination of objects/shapes

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

Unencapsulated sensory receptors

A

Merkel Cells
Free nerve endings
root hair plexus

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

Where are free nerve endings and what do they help us with?

A

In papillary dermis and low epidermis - Good for high/low temperature, pain, itching, and also tactile

22
Q

Root Hair plexus

A

Web of sensory fibers surrounding the bases of hair follicles in reticular dermis to detect hair movement

23
Q

Encapsulated Receptors

A

Meissner’s Corpuscles
Lamellar/Pacinian Corpuscles
Krause End Bulbs
Ruffini Corpuscles

24
Q

Meissner’s Corpuscles

A

Also called Tactile corpuscle. Sensitive to light touch (concentrated on the fingers, foreskin, and lips)

Located just beneath the epidermis (in the dermal papillae)

Rapidly adapting Mechanoreceptor

25
Q

Pacinian Corpuscles

A

Also called Lamellar Corpuscles. Detect deep pressure changes and vibrations.

Very large receptor field. Located deep in the dermis.

Rapidly Adapting Mechanoreceptor

26
Q

Krause Ends Bulbs

A

Thermoreceptors for sensing cold temperatures.

Located in the penis and clittoris (genital corpuscles) and in the eye, lips, tongue, and trunk.

27
Q

Ruffini Corpuscles

A

Slowly adapting Mechanoreceptor

Sensitive to the stretch and torque of skin

28
Q

Temperature control in the skin

A
  1. Constrict arterioles = constrict blood = retain heat in cold situations
  2. Evaporative cooling using eccrine glands
  3. Dilate arterioles to give off heat
29
Q

Parts of the follicle

A

Cuticle - Outermost area of the shaft. Heavily keratinized squamous cells

Medulla - Most interior of the hair shaft. Moderately keratinized

Cortex - Between the root sheath and the medulla. Heavily keratinized and densely packed. Within it are dermal papilla, cells that produce signals that drive the growth of hair follicles (projects into the cortex)

30
Q

Stages of hair growth

A

Anagen - Long period of mitotic division

Catagen - Brief period of arrested growth and regression of the hair bulb

Telogen - Final long period of inactivity, hair shedding

31
Q

Discuss the 3 types of exocrine glands

A

Merocrine - Sometimes called Eccrine glands (major sweat glands of the human body). Makes granules and release chemicals

Apocrine - Granules “buds off,” taking part of the cell’s cytoplasm

Holocrine - Whole cell breaks down

32
Q

Endocrine vs paracrine

A

Endocrine - Sit on the basement membrane and dumps into the blood

Paracrine - Secrete signals that act on nearby cells

33
Q

Duct cells

A

Reabsorb sodium from the sweat to reduce loss of sodium

34
Q

What are melanocytes derived from?

A

From neural crest cells (and they are found in the SB)

35
Q

In the skin, what is the most superficial layer in which nuclei are present?

A

Stratum Granulosum

36
Q

Where does lamellar body secretion occur and for what purpose?

A

In the Stratum Granulosum

Forms a waterproofing boundary for the skin (secretes lipids)

37
Q

What purpose to desmosomes serve?

A

Because the epidermis is avascular, desmosomes create channels that permit the flow of nutrients and the movement of cells

38
Q

What type of proteins are prevalent in the SG?

A

Cysteine and histidine rich proteins that bind keratin filaments together

39
Q

How do basal cells, as the become keratinocytes, change to toughen the epithelium?

A

Cross-linking of the cytoplasmic proteins

40
Q

Langerhan’s cells

A

Dendritic cells (APCs that endocytose antigens and transport them to the lymph nodes, initiating the immune response)

41
Q

What staining would reveal Langerhan’s cells?

A

Antibody staining (CD1)

In a normal H&E stain, it is too hard to differentiate b/w these cells and keratinocytes

42
Q

Where is the highest concentration of melanosomes in the skin?

A

SS for darker skin

SB for lighter skin

43
Q

Function of melanocytes

A

Melanocytes make melanin that is packages into melanosomes

44
Q

Myoepithelial cells

A

Squeeze and force sweat through ducts (ducts reabsorb various ionic components of sweat)

45
Q

Sebaceous gland

A

Holocrine secretion of oily material to allow for waterproofing

46
Q

Goblet cell

A

Unicellular, merocrine gland that secretes mucus

47
Q

What type of gland is the thyroid?

A

Endocrine (b/c it does not have any ducts)

48
Q

Which organs have both exocrine and endocrine components

A

Liver and pancreas

49
Q

What cell types are prevalent in keratinocytes

A

Keratinocytes consists mainly have keratinized stratified squamous epithelium

50
Q

Sebum

A

The oily/waxy matter produced by sebaceous glands to lubricate and waterproof the skin

51
Q

Claudin

A

Primary protein component of tight junctions to stop water from permeating through

52
Q

Claudin is great for helping with tight junctions to stop the permeability of water, but where is the real permeability layer for the skin?

A

The lipid layer.

S. granulosum cells make ceramides which are incorporated into lamellar bodies

Histo/Physio (14.5) (4 decks)

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