Lecture 16: Integumentary System Flashcards
1
Q
What are Membranes composed of?
A
Epithelium (epidermis) and connective tissue (dermis)
2
Q
What are the 4 types of membranes?
A
Mucous, Serous, Cutaneous, Synovial
3
Q
Which Membrane makes up skin?
A
Cutaneous membrane
4
Q
What is the Epidermis of a Membrane?
A
Epithelium
5
Q
What tissue is the Demis of a membrane made of?
A
Connective tissue
6
Q
What is the Largest organ system?
A
The skin
7
Q
How much of the body mass does skin account for?
A
15%
8
Q
Why is skin a good indicator of health?
A
Because it is very accessible
9
Q
What are the accessory structures of the Integumentary system?
A
Exocrine glands, Hair and Nails
10
Q
How does the integumentary system respond directly to local influences?
A
Through calluses and scar tissue
11
Q
What are Exocrine glands?
A
Glands that put the secretion via a duct onto the environment of the epithelium
12
Q
What are Endocrine glands?
A
Glands that secrete directly into the bloodstream
13
Q
What are the Major functions of the Integumentary System?
A
- Barrier
- Thermoregulation
- Sensation
- Metabolic functions
- Socials functions
14
Q
How does Skin act as a barrier?
A
It bears the brunt of most injuries and recovers better than any other organ system
15
Q
How does skin Thermoregulate?
A
- Constriction and dilation of blood vessels
* Sweating
16
Q
What are the Metabolic functions of Skin?
A
- Vitamin D synthesis with UV rays
* Storage of energy as subcutaneous fat
17
Q
What social functions does Skin have?
A
Identity for all animals
18
Q
What is the function of Epithelium in the skin?
A
Covers the surface and forms the boundary from the outside world
19
Q
What is the function of connective tissue in the skin?
A
- Supports epithelial tissue
* Provides strength and resiliency
20
Q
What is the function of Muscle in the skin?
A
- Controls the diameter of blood vessels
* Adjusts hair position
21
Q
What is the function of Nerves in the skin?
A
- Controls the smooth muscle in the CT
- Generates sensation
- Stimulates exocrine glands
22
Q
How many layers does Epithelium have?
A
Multiple layers
23
Q
How many layers does the Epidermis have?
A
5
24
Q
What are the layers of the Epidermis from Bottom to Top?
A
Stratum Basale (germinativum) Stratum Spinosum Stratum Granulosum Stratum Lucidum Stratum Corneum
25
What is the thickest layer of the Epidermis?
Stratum Corneum
26
What do Keratinized Squamous cells produce in the Skin?
Keratin
27
What is Keratin?
A tough protein that helps epidermis with its protective properties
28
What is the Bottom layer of the Epidermis called?
Stratum Germinativum (Basal Layer)
29
How many types of cells is in the Stratum Germinativum layer?
3 types of cells
30
What is the deepest layer of the Stratum Germinativum composed of?
Large Basal Stem Cells
31
What do the Stem Cells in the Stratum Germinativum do?
They divide to give rise to new keratinocytes to replace the dead ones that flake off
32
What are the most abundant epithelial cells in the epidermis?
Keratinocytes
33
What do Keratinocytes do?
Synthesize Keratin
34
Which layer of the EPidermis forms the Basal Lamina?
Stratum Germinativum
35
What does the Basal Lamina ensure?
It ensures that the epithelium is firmly attached to the basal membrane with connective tissue
36
What two types of cells are found in Stratum Germinativum?
Merkel (tactile) cells and Melanocytes
37
Of the cell types found in the Stratum Germinativum which one is less common?
Merkel (tactile) cells
38
Where are Merkel (tactile) cells more abundant?
Where skin has no hair (fingertips, lips)
39
What are Merkel (tactile) cells important for?
Touch sensation
40
When are Merkel (tactile) cells called Tactile (Merkel) discs?
When it is connected with a dermal nerve fibre
41
What layer of the Epidermis are Melanocytes found?
Stratum Germinativum
42
What do the Processes on Melanocytes do?
Insert themselves between Keratinocytes
43
What do Melanin granules produced by Melanocytes do when in the presence of Keratinocytes?
Melanin granules are phagocytized by Keratinocytes and form an umbrella over the nucleus to prevent DNA from UV radiation
44
What does the number of Melanocyte cells depend on?
The region of the body (ex. Palm of hand) but NOT by people
45
What determines skin tone?
The activity of Melanocytes and how many melanin granules they have, not the amount of melanocytes
46
What is another name for the Stratum Spinosum layer of the Epidermis?
Spiny Layer
47
What cells are the Stratum Spinosum composed of?
Several layers of keratinocytes and Langerhans (dendritic) cells
48
What do the Keratinocytes in the Stratum Spinosum contain?
A bundle of Tonofilaments
49
What are Tonofilaments and what do they do?
Keratin protein filaments that cause the cell to flatten and reach for neighbouring cells
50
What attach Keratinocytes together?
Desmosomes
51
What occurs in the Stratum Spinosum?
Keratinocytes flatten and reach for each other and desmosomes attach keratinocytes together
52
In what layer are Langerhans (dendritic) cells found?
The Stratum Spinosum
53
What forms Desmosomes?
Tonofilaments
54
What are Langerhans (dendritic) cells?
A type of macrophage that originates from bone marrow and migrate to epidermis
55
Where do Langerhans (dendritic) cells originate?
The bone marrow
56
What type of cells are Langerhans (dendritic) cells?
Macrophages
57
What do Langerhans (dendritic) cells do?
Capture pathogens and offer them to the immune system
58
How do Langerhans (dendritic) cells play an important role?
They are important for the immune response if pathogens penetrate the superficial layer
59
Where are Langerhans cells found in great numbers?
Oral cavity, esophagus, anal canal, and vaginal canal
60
What is the Stratum Granulosum composed of?
2-5 layers of flat keratinocytes
61
What does the Stratum granulosum produce?
Large quantities of keratohyalin granules
62
What do Keratinocytes in the Stratum granulosum secrete?
Lipid filled membrane coating vesicles that fill spaces between keratinocytes and form water-repellent sealant
63
What do the lipid-filled membranes secreted by keratinocytes in the Stratum Granulosum do?
Fill spaces between keratinocytes and form water-repellent sealant
64
What does the Sealant secreted by the keratinocytes of the Stratum Granulosum ultimately do?
Prevents cell diffusion that leads to keratinocyte death above the granular layer
65
Where in the body would you find excess production of the sealant produced?
In thicker skin like sole of foot and palm of hand
66
What does excess production of the sealant lead to?
Calluses
67
What is Keratinization?
Accumulation of keratin from deep to superficial layer
68
In what parts of the body is the Stratum Lucidum layer found?
In areas with thick skin and no hair like the palm of the hands and the bottoms of the feet
69
What does the Stratum Lucidum (clear layer) contain?
Large amounts of keratin and thickened plasma membranes. The cells have no nucleus or organelles
70
What is the most superficial layer of the skin?
The Stratum Corneum
71
What is the Stratum Corneum composed of?
Multiple layers of flattened, dead, interlocking keratinocytes (up to 30 layers)
72
What is the shedding of the Stratum Corneum known as?
Dander
73
What is Dandruff?
Clumps of dander from the Stratum Corneum stuck together with oil from the scalp
74
What is the main function of the Stratum Corneum?
Protection against abrasion and microbial invasion
75
How long does it take to go from the Basal layer to the Stratum Corneum?
30-40 days
76
What does the peak and valley interface between the dermis and epidermis allow for?
A tight bond between different layers of skin that can resist shearing stress
77
What are the two components of the Interface between the dermis and epidermis?
The Epidermal ridge and the Dermal Papilla
78
Which areas have a tall Dermal Papillae and why?
Sensitive areas (lips, genitals) to allow nerve fibers and capillaries closer to the surface
79
Where is the Interface very unique?
In the fingertips
80
What are the two layers of the Dermis?
The Papillary layer and the Reticular layer
81
Which layer of the Dermis is the connection to the epidermis?
The Papillary layer
82
What is the Papillary layer of the dermis composed of?
Areolar connective tissues (loose CT) that contains nerve ending and many capillaries
83
What does the Papillary layer of the dermis contact with the epidermis vary with?
The area of the body
84
What kind of tissue is the Papillary layer of the dermis composed of?
Areolar connective tissue (loose CT)
85
What kind of tissues is the Reticular layer of the Dermis composed of?
Dense irregular connective tissue, collagen bundles and elastic fibres
86
What does the Reticular layer of the dermis allow for in the skin?
Extensibility and elasticity to skin
87
What sits in the reticular layer of dermis?
Blood vessels, nerves, lymphatics, hair follicles, glands, adipocytes between fibre bundles, attachment to skeletal muscles of the face
88
What do Collagen fibers of the dermis align themselves with?
the areas of natural tension
89
What are Stretch Marks?
Scarring due to internal damage of collagen bundles and stretching of vasculature. Red = tearing of vessels, white = lack of vasculature after tearing
90
What is another name for the Hypodermis?
Superficial fascia or subcutaneous tissue
91
What does the Hypodermis do?
Stabilizes the position of skin relative to underlying tissues
92
What kind of tissue is the Hypodermis made of?
Loose connective tissue
93
What does the Loose Connective tissue of Hypodermis store?
Fat
94
What does the Fat of the Hypodermis do?
Pads the body, serves as energy reservoir, provides thermal insulation
95
What 3 Pigments are responsible for skin tone?
Melanin, Hemoglobin, Carotene
96
What colors is melanin responsible and which layer of skin is it found in?
Yellow/tan/brown/black and in Stratum basale and spinosum
97
What stimulates melanin synthesis?
UV stimulus
98
What is Hemoglobin?
The red pigment found in dermal blood vessels that gives skin a pink hue
99
What color does Carotene give to the skin and where is it found?
Yellow/orange in stratum corneum and hypodermis
100
What color is Cyanosis and what does it demonstrate?
Blue and lack of O2
101
What is erythema and what color is it?
Pooling of RBCs and Red
102
What color is Jaundice and what does it signify?
Yellow and excess bilirubin
103
What does Paleness signify?
Low blood flow
104
What color are hematomas and what do they signify?
Bruising - clotted blood, purple
105
What can destroy skin?
Excess UV radiation, heat, electricity, chemicals
106
What does Tissue Damage do to skin?
Destroys skins important contribution to homeostasis: protection against microbial invasion, dehydration, regulation of body temperature, alters composition of dermis and forms premature wrinkling
107
Which layer of the skin is affected in a 1st degree burn?
The epidermis
108
What are the characteristics of 1st degree burns?
Mild pain, erythema, flaking
109
Which layers of the skin are affected in 2nd degeee burns?
Epidermis and some dermis
110
What are the characteristics of 2nd degree burns?
Blister formation, edema, redness, pain and scarring after 3-4 weeks
111
Which layers are involved in third degree burns?
All layers through to the hypodermis
112
What are the characteristics of 3rd degree burns?
Skin functions lost, numb (no sensory ending), granulation forms, skin grafting may be needed
113
What are the 3 types of glands?
Merocrine, Apocrine, Holocrine
114
What is an example of a Merocrine gland?
A sweat gland
115
What is an example of an Apocrine gland?
Mammary gland
116
What is an example of a Holocrine gland?
Sebaceous gland
117
How do Merocrine glands secrete?
Normal exocytosis
118
How do Apocrine glands secrete?
The Apical surface is pinched off
119
How do Holocrine glands secrete?
The release the entire cell
120
What are the 4 types of Exocrine Cutaneous Glands?
1. Sweat glands
2. Sebaceous glands
3. Ceruminous glands
4. Mammary glands
121
What do Sweat glands secrete?
Water and Electrolytes
122
What are the two types secretion that Sweat Glands use?
Merocrine secretion (most common) & Apocrine secretion (puberty)
123
What do Sebaceous glands secrete?
Oily lipid (sebum) that coats hair and skin surface
124
What do Ceruminous glands secrete and through what type of secretion?
Earwax through apocrine secretion
125
What do Mammary glands secrete?
Breast milk
126
Where are Apocrine Sweat Glands found?
Axilla, groin, breast areola, male facial hair
127
What are Apocrine sweat glands strongly influenced by?
Hormones
128
What produces odor in Apocrine sweat glands?
Bacteria
129
When are Apocrine sweat glands activated?
During emotional stress and arousal
130
What do Merocrine sweat glands secrete?
Water and electrolytes (regular sweat)
131
Where are Merocrine sweat glands the most numerous?
On the Palms, soles, and forehead
132
What do Merocrine sweat glands regulate?
Body temperature
133
What are Merocrine sweat glands controlled by?
The sympathetic nervous system
134
What are Mammary glands regulated by?
Interaction of sexula and pituitary hormones
135
What does the Sebum from Holocrine glands inhibit?
Bacterial growth
136
What do Sebaceous glands usually open onto?
A hair follicle but some grow directly onto skin
137
What do Sebaceous glands do?
Keep hair and skin from becoming dry, brittle, and cracked
138
What causes Acne?
Inflammation of sebaceous glands and follicles due to blocked ducts and bacterial infection
139
What are Hair and Nails composed of?
Dead keratinized cells with HARD keratin
140
What is a Pilus (pili)?
A slender filament of keratinized cells that grow from a tube (follicle)
141
What surfaces does hair not cover?
Hands, feet, lips, nipples and genitals
142
How does hair differ from person to person?
Texture and pigmentation
143
What are the 3 types of hair?
Lanugo
Vellus
Terminal hair
144
Describe Lanugo
Fine hair from Foetus to birth
145
Describe Vellus
Most hair on body surfaces
146
Describe Terminal Hair
Longer, coarser and pigmented
147
What is Hair important for?
UV protection and thermal insulation for head, particle filtration for eyes and nose, touch sensation for the body
148
What are the 3 parts of the hair follicle?
Shaft, Root, Bulb
149
What two sheaths do Hair follicles have?
Epithelial root sheath and a CT root Sheath
150
Which sheath are Hair Neve fibers found?
The Epithelial root sheath
151
What do Arrector Pili muscle in hair follicles do?
Make the hair stand up to trap heat and is stimulated by the sympathetic nervous system
152
Which part of the hair follicle is above the skin?
The shaft
153
Which part of the hair is in follicle?
The root
154
Where does the Bulb of hair originate?
The Dermis
155
What is the Sole source of nutrition for the hair?
The papilla that has blood vessels
156
What changes the curl of the hair?
The cross sectional shape
157
What changes the texture of hair?
Keratin
158
What is color of hair determined by?
Pigment in the cells of the cortex
159
What are the 3 layers of hair from inside to outside?
Medulla, Cortex, Cuticle
160
What is in the Cortex of hair made out of?
Densely packed Keratinized cells
161
What is the Cuticle of hair?
Single layer of scaly cells that resist pulling on hair
162
What are the 3 stages of hair growth and hair loss?
Growth stage, Regression stage, Resting stage
163
What occurs in the Growth stage of hair?
Stem cells from bulge multiply and are added to the root as they push upwards they keratinized and die
164
How long does the growth stage take?
3-6 years
165
What occurs in the regression stage?
Cells stop dividing, follicle trophies and hair stops growing
166
How long does the regression stage take?
2-3 weeks
167
What occurs in the resting stage?
Hair loses it anchorage and old hair root falls out/push out of the follicle and new division occurs
168
How long does the resting stage take?
3 months
169
What stage is the majority of hair cells in?
Growth stage (85%)
170
What is the white part at the base of nail known as?
Eponychium (cuticle)
171
What is the part of the nail that we cut known as?
The free edge
172
What is the little piece of skin under the part of the nail that we cut known as?
Hyponychium
173
What is the part where the outside meets the nail known as?
The Eponychium
174
Why are nails pink?
Because of oxygen in the dermal layer
175
What is the Cuticle made of?
A band of epidermis
176
What is the nail made of?
Hard keratin
