Brainscape's Knowledge GenomeTM

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


See full index

Histology > Integument > Flashcards

Integument Flashcards

1
Q

Skin percentage body mass

A

15-20%

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

Skin functions

A

. Protection against mechanical assaults
. Barrier to biological and chemical and physical agents including UV radiation
. Moisture control
. Thermoregulation
. Sensory reception
. Metabolism (synthesis of vit. D3, removal of excess of electrolytes in sweat)

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

Epidermis

A

. Continuously proliferating stratified squamous keratinized epithelium
. Keratinocyte is principal cell
. Includes melanocytes, langerhans cells, Merkel cells
. Thick/thin skin based on thickness of epidermis only (thick on sole of foot and palm of hand, thin everywhere else)

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

Dermis

A

. CT, blood vessels, nerves, sensory receptors, and skin appendages
. Epidermis and dermis bound by specialized basement membrane
. Rete ridges: epidermal down growths that extend into superficial dermis and result in formation of dermal upward projections (dermal papillae)

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

Hypodermis

A

. SubQ

. Often not soldiered part of skin

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

Where is the thickest skin?

A

Upper portion of back

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

Keratinocytes

A

. Arise from deepest layer of epidermis
. Move toward free surface as they differentiate
. Contain keratin
. During differentiation they lose mitotic abilities but continue to produce keratin
. Keratin represents about half of total protein in superficial cell layer

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

Basal layer of epidermis (stratum basale)

A

. Single layer cuboidal cells separated from dermis by basement membrane
. Hemidesmosomes bind cell to basal lamina
. Desmosomes bind cells to each other
. Keratinocytes frequently under mitosis

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

Human epidermis renewed every ____

A

15-30 days

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

Spinous layer of epidermis (stratum spinosum)

A

. Prickle cell layer
. Thickest layer
. Keratinocytes produce cytoplasmic intermediate filaments (cytokeratins)
. Cytokeratins form bundles (tonofilaments)
. Aggregates of tonofilaments (tonofibrils)
. Tonofibrils bind to desmosomes btw adjacent keratinocytes

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

Granular layer of epidermis (stratum granulosum)

A

. 3-5 layers of flattened cells undergoing keratinization
. Cytoplasm contains basophilic keratohyalin granules and filaggrin protein w/in granules and lamellar granules (golgi-derived w/ lipids)

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

Stratum lucidum

A

. Only in thick skin

. Thin layer flattened keratinocytes w/ lost nuclei and organelles and packed keratin filaments

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

Stratum corneum layer in epidermis

A

. 15-20 layers of keratinized cells filled w/ keratin filaments

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

Melanocytes

A

. Derived from neural crest
. Synthesize melanin that absorbs UV radiation
. Located in stratum basale w/ long processes into stratum spinosum
. Functionally related to 4-10 keratinocytes forming epidermal-melanin unit
. Sends melanosomes to keratinocyte cytoplasm

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

Carotene

A

Yellow pigment in skin and adipose that affects skin color

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Langerhans cells

A

. Antigen-presenting cells derived from bone marrow

. 2-8% epidermal cells mostly in stratum spinosum

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

Merkel cells

A

. Mechanoreceptor cell that detect light touch
. Located in stratum basale
. Joined by desmosomes to keratinocytes

18
Q

Papillary dermis

A

. Dermis immediately adjacent to epidermis

. Has fine collagen fibers and small blood vessels, sensory nerve endings and structures

19
Q

Reticular dermis

A

. Deeper, dense irregular CT rich in collagen and elastic fibers

20
Q

Dermis functions

A

. Responsible for tone and texture of skin

. When aging the collagen and elastin in upper dermis degenerate and skin loses texture and wrinkles

21
Q

Nerve endings found in dermis

A

. meissner’s corpuscles: touch receptors found in papillary dermis
. Pacinian corpuscles: deep pressure receptors in deep dermis and hypodermis
. Ruffini corpuscles: stretch and tension receptors in deep dermis
. Krause end bulbs: mechanoreceptors found in lining of oropharynx and conjunctiva of the eye

22
Q

Hypodermis

A

. Loose CT and adipose
. Binds skin loosely to subadjacent organs
. Compartmentilized by fibrous septa running from deep reticular dermis to fascial tissue that underlies hypodermis
. Larger vessels that supply and drain dermal blood vasculature

23
Q

Sebaceous glands

A

. Produce sebum (skin lubricant w/ slight antibiotic effect)
. Assoc. w/ hair follicles usually, but can be unrelated (eye like, oral cavity)
. Cluster of 3-5 alveoli
. Secretory cells get larger as they accumulate lipid droplets
. Entire secretory cell is released as product (holocrine)

24
Q

Sweat glands

A

. Found everywhere but lip margins and parts of genitalia

. Most abundant on palm of hand and sole of foot

25
Q

. Eccrine sweat glands

A

. Simple coiled tubular glands formed by secretory portion (w/in deep reticular dermis) and excretory eccrine duct
. Becomes straight as it ascends vertically through dermis towards skin surface
. Secretory cells are clear, larger cells that secrete bulk of watery sweat and smaller cells that secrete glycoprotein
. Attenuated outer layer of myoepithelial cells that form discontinuous layer btw secretory cells and basement membrane

26
Q

Apocrine sweat glands

A

. Limited distribution
. Found in axilla and groin
. Secretory portion in deep reticular dermis or hypodermis
. Secretory portion located in deep reticular dermis or hypodermis and is coiled tubule w/ diliated lumen
. Secretory product discharged via ducts into upper parts of the hair follicle above sebaceous gland
. Not functional until puberty

27
Q

Where is hair not present?

A

. Skin of palms and soles
. Lip
. Parts of genitalia

28
Q

Components of hair

A

. Shaft: protrudes above the surface of the epidermis

. Root: embedded in skin

29
Q

Where does hair form?

A

. W/in epidermal invaginations in hair follicles

. In assoc. w/ sebaceous glands and smooth muscle bundle (arrector pili)

30
Q

Hair bulb

A

. Terminal dilation in hair follicle

31
Q

Dermal papilla

A

. Contains blood capillaries

. Inserts into base of hair bulb

32
Q

Keratinocytes continuous w/ ___ layer of epidermis to cover dermal papilla

A

.basal layer

33
Q

What occurs during active hair growth?

A

. Epithelial cells proliferate to form layers of hair follicle
. Undergo keratinization, melanin accumulation and maturation

34
Q

Medulla in regards to hair

A

. Center of hair root

35
Q

Cortex in regards to hair

A

. Heavily keratinized cels around medulla

36
Q

Hair cuticle

A

. Thin layer of keratinized cells covering cortex

37
Q

Root sheath

A

. Continuous w/ outermost cells of hair bulb
. Internal root sheath: surrounds initial part of hair root but degenerates over sebaceous gland level
. External root sheath: covers internal sheath and extends to epidermis and is continous w/ strata basale and spinosum

38
Q

Nails

A

. Hard players of keratin on dorsal surface of each distal phalanx
. Nail root covered by fold of skin and has cuticle/eponychium (extension of stratum corneum)
. Bound to nail bed (bed of epidermis w/ stratum basale and spinosum)

39
Q

How is nail root formed?

A

From nail matrix

. Cells divide, move distally and become keratinized

40
Q

Hyponychium

A

. Epidermal fold where distal end of nail plate becomes free of nail bed

Histology (22 decks)

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