Integumentary: slide 19 on Flashcards
1
Q
Coloring from carotene:
- what colors?
- acquired from?
- accumulates inside?
A
- Yellow-orange pigment
- Acquired from yellow-orange vegetables
- Accumulates inside subcutaneous fat and keratinocytes of stratum corneum
2
Q
Nevus is commonly called ______
A
a mole
3
Q
Nevus=
A
- Harmless overgrowth of melanin forming cells
- Rarely may become malignant
4
Q
Freckles= represent localized areas of _____
A
- Yellowish or brown spots
- –> localized areas of increased melanocyte activity
- Degree of pigmentation based on sun exposure and heredity
5
Q
Ridge patterns of the skin:
- Friction ridges?
- locations?
- what are they formed by?
A
- Friction Ridges (fingerprints)
- located on fingers, palms, soles, and toes
- formed from large folds and valleys of dermis and epidermis
6
Q
T/F: each individual has a unique pattern of friction ridges
A
True
7
Q
Friction ridges: function?
A
- *help increase friction on contact
- allows for personal identification
8
Q
Dermis: divided into 2 layers
A
- papillary layer
- reticular layer (deep)
9
Q
Describe the papillary layer of the dermis:
- -where is it located?
- made of which type of CT?
A
=Superficial 20% thickness of the dermis, directly adjacent to epidermis
-Composed of areolar connective tissue
Derives name from projections of the dermis termed dermal papillae
-contain capillaries that supply nutrients to epidermis
10
Q
Papillary layer of the dermis:
projections of the epidermis interdigitating with papillae termed _______ _______
A
**epidermal ridges
11
Q
Papillary layer of the dermis: Interlocks between dermal papillae and ________ ______, which increases the area of contact between layers
A
epidermal ridges
12
Q
Describe the Reticular layer of the dermis:
-which type of CT?
A
=Deeper 80% thickness of the dermis, extends from papillary layer to subcutaneous layer
-*Consists primarily of dense irregular connective tissue containing collagen and elastic fibers
13
Q
Reticular layer of the dermis contains which structures:
A
- hair follicles, sweat glands, sebaceous glands
- Collagen and elastic fibers oriented in parallel bundles
14
Q
Reticular layer of the dermis: the collagen and elastic fibers oriented in parallel bundles serve to?
A
- Alignment result of applied stress during routine movement
- Bundles functioning to resist stress
- Orientation indicated by lines of cleavage (tension lines)
- Important consideration for surgery (incisions parallel to cleavage lines heal quickly)
15
Q
An incision perpendicular to cleavage lines may ____
A
**gape and delay healing.
16
Q
An incision parallel to
cleavage lines is more
likely to _____
A
heal quickly and
not gape open.
17
Q
Innervation & blood supply of the dermis (2 things)
A
- Dermis with extensive nerve fibers
- Dermal blood vessels
18
Q
Innervation & blood supply of the dermis:
-describe the extensive nerve fibers
A
- Sensory nerve fibers detect pain, temperature, touch, vibration,
- Motor nerve fibers control blood flow and gland secretions
19
Q
Innervation & blood supply of the dermis:
-describe Dermal blood vessels (small vs large?)
A
- Supply nutrients to epidermis and dermis
- Large vessels along reticular and subcutaneous border
- Smaller vessels branching into dermis and dermal papillae
- Play an important role in body temperature and blood pressure regulation via vasoconstriction and vasodilation
- -*Vasoconstriction (blood vessel diameters narrowed, blood shunted from periphery toward deeper structures, occurring when trying to conserve heat)
–**Vasodilation (blood vessel diameter increased, more blood close to body surface, occurs when needing to loose heat)
20
Q
Subcutaneous layer, aka
A
- subcutaneous tissue, superficial fascia, hypodermis
- **Not a part of the integument
21
Q
Describe the structure of. the subcutaneous layer.
A
- predominantly adipose CT, small amount of areolar CT
- highly vascularized
- Connective tissue fibers interwoven with those of reticular dermis
22
Q
Function of the subcutaneous layer
A
- energy storage, insulation, cushion
- anchors the skin to underlying structure (mostly to muscles) & allows the skin to slide relatively freely over those structures
23
Q
T/F: different sexes have different layered thickness and distribution of the subcutaneous layer
A
True!
- women, generally thicker, primarily in breasts, buttocks, hips, and thighs
- men, generally thinner, primarily in neck, upper arms, abdomen, lower back, buttocks
24
Q
Integumentary structures derived from the epidermis:
- formed from portions of the epidermis invaginated into the _____.
- List the 6 structures they include
A
dermis
Including:
- Nails
- Hair
- Merocrine sweat glands
- Apocrine sweat glands
- Sebaceous glands
- Ceruminous glands
25
Hair is found almost everywhere on the body except:
- the hands and palmar surface of the fingers
- the sides and soles of the feet and toes
- the lips
- portions of the external genitalia
26
Describe--> hair composition
Composed of keratinized cells growing from hair follicles
27
Describe the structures included in a hair bulb:
- hair papilla
| - matrix
28
What structures are included in the hair root:
- cuticle
- medulla
- cortex
- Hair follicle
- connective tissue root sheath
29
What structures are included in the hair follicle?
- CT root sheath
| - epithelial tissue root sheath
30
Describe the hair bulb:
- where does swelling occur?
- What does it surround?
- swelling at the base where hair originates in dermis
| - surrounds hair papilla, (projection of dermis which provides the hair with nutrients)
31
Describe the hair bulb:
| -what is immediately above the hair papilla?
- Immediately above the hair papilla is a region called hair matrix, it’s the hair growth center, and is composed of mitotically active keratinocytes, the produced new cells gradually pushed toward surface
- **the hair pigments are made by melanocytes in hair matrix.
32
Hair structure:
| -the root?
=the portion of dead keratinized cells penetrating into dermis and sometimes into subcutaneous layer
33
Hair structure:
| -the shaft?
portion of hair beyond skin surface
34
```
Hair structure"
describe the following:
-medulla
-Cortex
-cuticle
```
medulla= composed of loosely arranged cells and air space. Contains flexible, soft keratin
Cortex=flattened cells closer to outer hair surface. relatively hard
Cuticle=single cell layer around cortex
35
Hair follicles:
| -are oblique ____ surrounding the hair root
tubes
36
Hair follicles:
| -extend into?
dermis and sometimes subcutaneous layer
37
Hair follicles:
| have an outer ______?
**has outer connective tissue root sheath originating in dermis
38
Hair follicles:
| -has an inner ______?
has inner epithelial tissue root sheath originating from epidermis
39
Arrector Pilli:
- thin ribbons of_____?
- extends from?
-Thin ribbons of smooth muscle
-Extend from hair follicle to the dermal papillae
-Elevates hair with contraction, producing “goosebumps”
Protection
40
Functions of hair (list 5)
- Protection
- Heat retention
- Sensory reception
- Visual identification
- Dispersal pheromones
41
Describe the mechanism of Protection (fx of hair)
- Protects scalp from sunburn and injury
- Hair within nostrils trapping particles
- Hair within ears protecting from foreign matter
- Eyelashes protecting eyes
- Eyebrows keeping sweat out of eyes
42
Describe the mechanism of heat retention:
Prevents loss of heat from scalp to air
43
Describe Sensory reception
-Has associated tactile receptors
44
Describe the mechanism of Visual identification (fx of skin)
Important in determining age, sex, specific individuals
45
Describe the mechanism of dispersal pheromones (skin fx)
- chemical signals involved in attracting sexual partners
| - secreted by specific sweat glands onto hairs in axillary and pubic regions
46
List the 3 kinds of exocrine glands of the skin
- apocrine
- merocrine
- sebaceous
47
Merocrine (Eccrine) Sweat Glands:
- how many are there?
- where are they located?
Most numerous and widely distributed, abundant in palms, soles & forehead; absent in some genital regions, lips, nipples
48
Merocrine (Eccrine) Sweat Glands:
| -function?
- Discharge their secretions onto skin surface,
- Produce secretions by exocytosis
- -**Secrete sweat
49
Describe the composition of sweat:
- composed of 99% water and 1% other chemicals
| - include electrolytes, metabolites, and waste products (urea, uric acid, ammonia
50
Functions of the Merocrine (eccrine) sweat glands (4)
- Regulation of body temperature by fluid evaporation
- Provide a means for loss of water and electrolytes
- Secretions diluting harmful chemicals
- Secretions with antibacterial activity
51
Apocrine Sweat glands:
| -found in?
- Found in axillae, around nipples, in pubic and anal region
| - -Discharge their secretions into hair follicles
52
Apocrine sweat glands produce secretions by ______
exocytosis
- Produce viscous, cloudy secretions called pheromones (estrogen- and progesterone-like secretions)
- Start producing secretions during puberty for communication
53
Sebaceous glands:
| -are ______ distributed
widely
54
Sebaceous glands: fx
| hint: what do they produce?
- Produce oily secretion called sebum
- Holocrine glands
- Secretion stimulated by hormones, especially androgens
- Activated during puberty
55
Describe Sebum
- acts as a lubricant for skin and hair
- has bactericidal properties
- discharged into a hair follicle
56
Sebaceous glands (summary):
- locations?
- Secretion?
- functions?
1. locations - widespread
2. secretion
- -contains sebum (oil) and cellular fragments
- -secreted by destruction of the whole glandular cells (holocrine gland), secreted into hair follicles rather than directly to skin surface
3. functions - lubrication, prevents water loss, keeps skin and hair from becoming dry, brittle, and cracked, inhibits bacterial growth
57
Ceruminous glands= modified ______ sweat glands
apocrine
58
Ceruminous glands:
- location?
- secretions?
-**Located only in the external acoustic meatus
- Secretions form waterproof earwax, cerumen
- -help trap foreign material
- -help lubricate acoustic meatus and eardrum
59
Mammary glands= modified ______ sweat glands of the breast
apocrine
60
Mammary glands:
| -function?
- Only function in pregnant and lactating females
| - Produce milk – nutrient for infants
61
Functions of the integument: Epidermis (list 7 functions)
- protection
- Prevention of water loss
- production of vitamin D3 (cholecalciferol)
- Secretion
- Absorption
- Immune Function
- Sensory Reception
62
Functions of the integument- Epidermis:
| -describe the mechanism of protection
- Protects body from physical injury and trauma
- Protects from chemicals, toxins, microbes, temperature extremes
- Protects deeper tissue from solar radiation
63
Functions of the integument- Epidermis:
| -describe the mechanism of prevention of water loss
- Helps prevent unnecessary water loss
- Water resistant, NOT waterproof--some interstitial fluid penetrating through epidermis to air (a process termed transpiration)
64
Functions of the integument- Epidermis:
| -describe the mechanism of production of vitamin D3 (cholecalciferol
- Stimulated by UV light - steroid in keratinocytes is converted to vitamin D3
- Vitamin D3 is transported to an intermediate molecule in liver
- The intermediate molecule is converted to calcitriol (an active form of vitamin D) which is a hormone that stimulates absorption of Ca and P in intestine)
65
Functions of the integument- Epidermis:
| -describe Secretion
- Plays a role in electrolyte homeostasis by secreting waste products onto skin surface during sweating
- Sebum of sebaceous glands lubricating skin surface and hair
66
Functions of the integument- Epidermis:
| -describe Absorption
Can absorb certain chemicals and drugs
67
Functions of the integument- Epidermis:
| -describe immune fx?
-Dendritic cells in stratum spinosum in epidermis (also present in dermis) initiate immune response against pathogens, attack cancer cells
68
Functions of the integument- Epidermis:
| -describe sensory reception
Detect light touch
69
Function of the integument: Dermis (list 3 functions)
- temperature regulation
- Sensory reception
- some shared function with epidermis (E.g., secretion and absorption and immune function)
70
Describe Temperature regulation (fx of the Dermis)
- Blood vessel dilation and sweating when body too warm
- Blood vessel constriction when body too cold
- Evaporative cooling at surface (sweat gland)
71
Describe Sensory reception (fx of the dermis)
Detect heat, cold, touch, pressure, and vibration
