integumentary system online module part 2 W6 Flashcards
1
Q
what is the dermis
A
the layer of connective tissue that lies directly beneath the epidermis
2
Q
what is the purpose of the dermis
A
to support the epidermis both metabolically and structurally (strength and flexibility)
3
Q
what are the accessories of the skin that the dermis contains (5)
A
hair folicles sebaceous glands sweat glands blood and lymphatic vessels nerve fibres and sensory receptors
4
Q
what are the two types of connective tissue that make up the dermis
A
loose and dense irreg CT
papillary and reticular dermis
5
Q
what is the name of the loose connctive tissue region that lies directly beneath the epidermis
A
papillarylayer
6
Q
what does the papillary layer form
A
dermal papilla between the epidermal pegs
7
Q
whereis the reticular dermis found
A
between the papillary layer and the hypodermis
8
Q
what is the reticular dermis made out of (tissue type)
A
dense irreg CT
9
Q
what are the main fibres found in the dermis
A
collagen
elastic fibres
10
Q
whats the best way to stain elastic fibres
A
orcein stain (stains elstic fibres black)
11
Q
why are collagen fibres usually found running alongside elastic fibres
A
to resist and prevent overstretching
12
Q
what layer is found beneath the dermis(3 diff mnames)
A
the subcutus, or the subcutaneous layer, or the hypodemis
13
Q
is the hypodermis /subcutaneous layer partof the skin
A
no
14
Q
is the hypodermis / subcutaneous layer part of the integumentary system?
A
yes
15
Q
what makes up the hypodermis? (2)
A
CT and adipose tissue
16
Q
sometimes the bottom of …. …. can be seen extending down into the hypodermis
A
hair follicles
17
Q
what are the four different types of sensory innervations of the the skin (sensory components)
A
free nerve endings
markel cells
meissner’s corpuscle
pacinian conpuscle
18
Q
what do free nerve endings detect (2)
A
temperature changes and pain
19
Q
what do merkel cells and meissner’s corpuscles detect (1)
A
touch
20
Q
what do pacinian corpuscles detect
A
pressure and vibration
21
Q
where are free nerve endings found (2)
A
epidermis and dermis
22
Q
where are merkel cells found
A
stratum basale of the epidermis
23
Q
where are meissner’s corpuscules found
A
in the papillary dermis
24
Q
where are pacinian corpuscles found
A
in the reticular dermis (extending as far down as the hypodermis
25
what does this pic depict ?
pacinian corpuscle
26
what does this pic depict ?
meissner's corpuscle
27
what are the four primary appendages of the skin
hair / hair follicles
nails
sebaceous glands
sweat glands
28
what are two appendages are commonly found together
sebaceous glands and hair/hair folicles
29
what are sebaceous glands and hairfollicles called as a siglular structure
pilosebaceous apparatus
30
hair follicles are down growths of the ....
epidermis
31
where are arrector pili muscles found
connect to hair follicles
32
what is the name of the muscles that is found connecting to a hair folicle
arrector pili muscle
33
what type of muscle comprises the arrector pili muscle
smooth muscle
34
what is the hair shaft made up of (3) out --> inside
cuticle
cortex
medulla
35
where oes hair begin growth
hair bulb
36
what occurs in the hair bulb
lots of mitosis
37
what cells are found in hair bulbs
melanocytes
38
what does the hair bulb contain ( hint .. specialised area of the .....)
dermis
39
what is the specialised are of the dermis within a hair bulb called
papilla dermis
40
what is within the papilla dermis (3 main components)
lots of nerves, blood vessels, mesenchymal stem cells
41
what produces the hair shaft and where does this occur
lots of actively dividing stem cells produce hair shaft (and other layers of hair follicell
within the papilla dermis inside the hair bulb
42
what happens in melanocye cells run out in the hair papilla ( inside the hair bulb)
your hair turns grey
43
what is the matrix
a number of diving cells which go on to form the hair shaft and the outer layers of hair folicel
44
what do melanocytes do in the hair papilla in the hair bulb,
give hair its colour
45
what are these thing on the pic
hair follicels
46
what are the two types of keratin
hard and soft
47
what determines the hardness or the softness of the keratin
the levels of sulfation the keratin has undergone
48
lots of sulfur = ......keratin
hard
49
little sulfur = ....keratin
soft
50
epidermal keratin is ..... sulfated and therefore ....
less and therefore
| soft
51
hair/nail keratin is .... sulphated and therefore ...
more and therefore
| hard
52
what are the three glands of the skin
sebaceous
eccrine sweat glands
apocrine sweat glands
53
what is another name for apocrine sweat glands
odoriferous glands
54
what do sebceous glands secrete and via what more of secretion
holocrine secretion of sebum
55
what do eccrine glands glands secrete and via what more of secretion
merocrine secretion of sweat
56
what do Apocrine /odoriferous glands glands secrete and via what more of secretion
merocrine decreation of sweat
57
what prompts the release of sweat in apocrine/odoriferous glands
emotional response(eg fight or flight)
58
what prompts the release of sweat from eccrine glands
thermoregulation
| emotional response
59
what shape are sebaceous glands
simple branched acinar (sac like glands)
60
what do sebaceous glands contain
sebum
61
what is sebum
oily thick substance
| and is viscous and may be secondarily infected by bacteria (eg acne/pimples)
62
sebaceous glands open onto skin surface via ....
hair follicle
63
what type of glands are sebaceous glands
holocrine glands
64
activity of sebaceous glands may be controlled by ....
sex hormones
65
sebaceous glands contribute to the .... of the epidermis
lubrication
66
secretion of sebaceous glands are controlled by the .....
ANS (autonomic nervous system)
67
why cant lipid based secretions be exocytosed (they have to undergo holocrine or apocrine secretion)
because lipid droplets dont have a cell membrane
68
describe what is happening within this picture
(sebaceous gland process)
basal cells sit on basal lamina
basal cells undergo mitosis and one of the two daughter cells move out and become sebaceous gland cell, cells accumilate lipids and as they move towards the duct they undergo cell death, and the nucleus shape changes ( becomes picnotic nucleus)
69
what is a picnotic nucleus
deformed nucleus present in cells undergoing cell death
70
eccrine sweat glands shape
coiled tubular glands
71
eccrine sweat glands open onto the skin surface via....
duct
72
eccrine sweat glands are .....secreting glands
merocrine
73
the secretory portion of the eccrine sweat gland is located ...
deep in the dermis
74
sweat is a mixture of .....a dn ...... products
secretory and excretory
75
what are the two different forms of eecrine glands sweating (related to the causes of sweating)
thermoregulation and emotional
76
eccrine gland sweating is controlled by the .....
ANS (autonomic nervous system)
77
what are the three types of cells found in eccrine sweat glands
dark cells
clear cells
myoepithelial cells
78
what do dark cells in eccrine sweat glands contain?
proteinaceous secretion
79
what do clear cells in eccrine sweat glands contain?
watery secretion
80
what do myoepithelial cells in eccrine sweat glands do?
contract
81
the duct portion of the gland is amde up of....
stratified cuboidal epithelium
82
thermoregulatory sweating is ....... and is brought about by .......
cholinergic
| acetalcholene
83
emotional sweating is classified as ...... and is caused by .....
adrenergic
adrenaline
84
shape of apocrine sweat glands
simplecoiled tubular
| with wide secretory lumen
85
apocrine sweat glands open onto the skin via...
hair follicle
86
apocrine sweat glands secrete via ..... secretion
merocrine
87
the secretory portion of an apocrine sweat gland lies deep in the ...
dermis
88
apocrine sweat gland secretion is often ....(texture) and may become .......... ........
```
viscous
secondarily infected (eg body odour)
```
89
apocrine sweat glands are often found in ...... and ..... areas
axillary and anogenital
90
exapmle of gland in axillary and anogenital region
ceruminous gland in ear (wax)
91
mammary glands are also modified ..... glands
apocrine sweat glands
92
apocrine gland secretion is controlled by the ...
ANS autonomous nervous system
93
apocrine sweat glands are activated in response to only ..... stimuli
emotional (eg, arousal, or fight or flight (fear))
94
apocrine sweat gland activity may be controlled by...
sex hormones
95
where is axillary regions
armpits
96
what is this a picture of
apocrine glands
97
what are the (6) functions of the integumantary system
- protection of external environment
- vit D synthesis
- cutaneous sensation
- blood reservoir
- excrertion and absorption
- body temp regulations
98
functions of the integumentary system: protection from the external environment:
what features of the integumentary system play a part in this function..(11)
- stratified nature of the epithelium
- keratinisation - against miscrobes abreasion heat nad chemicals
- cell junctions - resists microbe invasion: holds cells together
- lipids from lamellar bodies coating suface cells - preventing water evaporation
- sebum: prevents skin from drying , cracking , exposing underlying tissue, and getting infected
- acidic pHof sweat- prevents some bad microbe growth
- melanin - uv protection far basal stem cells
- langerhans cells - protection against invading microbes
- transient and resident WBCs in dermis
- dermial papilae and epidermal pegs
- hairs and glands are a source of new skin ( they contain stem cells(as long as you have hairs and glands present, you have stem cells to produce more cells)
99
functions of the integumentary system: sensory perception
what features of the integumentary system play a part in this function..(4)
- free nerve endings
- merkel cells
- meissener's corpuscles
- pacinian corpuscles
100
```
functions of the integumentary system:
temperature regulation (homeostatis)
```
what features of the integumentary system play a part in this function..(3)
-eccrine sweat glands
-hair and 'goose
-bumps'
altered blood supply
101
functions of the integumentary system: blood resovior
how integumentary system play a part in this function..
in times of crisis blood can be diverted from the skin to areas requiring greater blood supply ( eg heart, skeletal muscle, brin etc) this may lead to increased body temperature
102
functions of the integumentary system: excetion and absorption (minor role)
what can be absorbed through the skin (3)
toxins
lipid soluble vitamins
some drugs (eg nicotene)
103
functions of the integumentary system: excetion and absorption (minor role)
what is excreted via the skin (3)
- 400ml water lost per day (evaporation)
- 200ml water lost per day (sweat)
- small amounts of salt, urea, ammonia, CO2 excreted via sweat
104
water absorbtion through the skin is...
negligable
105
functions of the integumentary system: Vitmain D synthesis
| expain how
Uv radiation activates precursors in the skin that are then enzymatically modified in the liver to form
CALCITROL the most active form of vitamin D
calcitrol is necessary for the uptake of calcium from alimentary tract
106
what is CALCITROL
the most active form of vitamin D
107
what is the name of the most active form of vit D
calcitrol
108
what is calcitrol necesary for
uptake of calcium from allimentary tract
109
what can insufficient calcium lead to (2)
rickets
| interfere with muscle and nerve activity
