Tissues and Integument (Sept 10) Flashcards
1
Q
Four types of tissue
A
- Epithelial (covering) 2. Muscle (movement) 3. Nervous (control) 4. Connective (support)
2
Q
Label 1 and 2
A
- Simple
- Stratified
3
Q
Label 1, 2, 3
A
- Squamous
- Cuboidal
- Columnar
4
Q
Label 1, 2, 3, 4
A
- Apical
- Lateral
- Basal
- Basement membrane
simple columnar epithelial tissue
5
Q
Connective tissue
A
- most abundant by weight
- well vascularized
- easily repaired (things in blood are connective tissue therefore it has good protection against infection)
- tissue repair
- insulation (heat, vibrations)
6
Q
Extra cellular matrix
A
- connective tissue consists of cells surrounded by extra cellular matrix
- ECM= ground substance +fibres (collagen, elastin, etc.)
- ground substance may be fluid, semi fluid, gelatinous, or calcified
- different amounts of fibre types and cell types produce different classes of connective tissue
7
Q
Connective tissue proper
A
Loose connective tissue: areolar, reticular, adipose
-main cell type: fibroblasts, adipocytes (semi-fluid GS)
Dense connective tissue: regular, irregular, elastic
-main cell type: fibroblasts (little GS)
8
Q
Cartilage
A
-main cell type: chondrocytes (stiff, gelatinous GS)
9
Q
Bone
A
- main cell type: osteocytes
- calcified GS for structural stability
10
Q
Blood
A
main cell type: RBCs (highly fluid GS with some proteins as well)
11
Q
cyanotic skin
A
- blue
- hypoxemia (low blood oxygen level)
- usually related to something in respiratory system
12
Q
jaundice skin
A
- yellow
- liver dysfunction
- old red blood cells that die and should’ve been eliminated accumulate under skin
13
Q
erythema
A
- red skin
- heat, infection, inflammation, allergic reaction
14
Q
pallor
A
- white skin
- shock, anemia, peripheral vasoconstriction (to divert blood to vital organs)
- inadequate blood to skin
15
Q
Integumentary System
A
- skin and accessory organs
- consists of two layers: epidermis, dermis
- sits on hypodermis (subcutaneous layer)
16
Q
Epidermis
A
- avascular
- get nurtients, etc. through diffusion
- epithelial tissue
- contains keratin
17
Q
Hypodermis
A
- largely adipose tissue
- connective tissue
18
Q
Dermis
A
- hair follicles
- glands
- sensory receptors
- blood vessels
- connective tissue
19
Q
Label the layers of epidermis
A
- Stratum corneum
- Stratum lucidum
- Stratum granulosum
- Stratum spinosum
- Stratum basale
20
Q
Stratum corneum
A
- 25/30 layers of dead cells
- thin, flattened cells
- just plasma membrane with keratin and starting to get loose (not really cells)
21
Q
Stratum lucidum
A
-only present in thick skin when you need toughness
22
Q
Stratum granulosum
A
- 3/5 layers of cells
- transition zone (living-dead)
- keratohyalin
- lamellar granules
- cells are far away from dermis and therefore far from blood vessels so they are not getting sufficient oxygen and blood to maintain life
- very tough layer with lots of keratin
23
Q
stratum spinosum
A
- 8/10 layers
- keratin intermediate filaments
- cells joined by desmosomes
- contains Langerhans cells (part of immune function)
- large cells
- keratin produced (strong tough protein that resists heat and waterproofs skin and connects the cells)
24
Q
stratum basale
A
- from which all other layers are derived
- germinates and grows epidermis (makes new cells to get pushed to surface)
- psoriasis: quickened process of cells moving from bottom to top (skin starts forming scales and flaking off)
- contains Merkel cells
- lots of division of cells in this layer
- melanocytes present in this layer which have projections into spinosum
25
Q
Keratinocytes
A
- in epidermis
- predominant cell type (90%)
- produce keratin
26
Q
Melanocyte
A
- 8% of epidermal cells
- produce melanin
- protects underlying cells in basale from UV radiation
- UV radiation can cause mutations when cells are dividing
27
Q
Langerhans cell
A
- intraepidermal macrophage
- phagocytosis
- stratum spinosum
- immune function
28
Q
merkel cell
A
- detect touch
- stratum basale
- connection with sensory neuron
29
Q
epidermal ridges
A
- gives rise to fingerprints
- increases surface area of epidermis (improves grip)
- increases contact between dermis and epidermis (better connection so epidermis doesn’t fall off as easily)
30
Q
label the diagram
A
- epidermal ridge
- epidermal peg
- dermal papilla
31
Q
what is melanin
A
- yellow/red or brown/black pigment
- everyone has same number of melanocytes but different amounts of melanin
- protects germinal layer against UV rays
- increased UV= increased melanin synthesis (keratinocytes sense UV which turns genes on inside so they start releasing melanocyte stimulating hormone to increase melanin production)
- also responsible for hair colour
32
Q
what is responsible for skin tone?
A
- melanin (mainly)
- carotene (vit A)
- hemoglobin
33
Q
albinism
A
-no melanin produced but they have melanocytes
34
Q
vitiligo
A
- loss of pigment in patches (autoimmune)
- melanocytes are being destroyed by immune cells so you see red/pink hue of dermis
35
Q
freckles/moles/melanoma
A
- aggregation of melanin/melanocytes
- cancerous mole (melanocytes start growing uncontrollably and will pull out of stratum basale, find a blood vessel, and spread to other areas
36
Q
features of dermis
A
- deeper and thicker than epidermis
- binds the epidermis to the underlying tissues
- contains collagen and elastic fibres that provide support for the skin (secreted by fibroblasts)
- contains blood vessels, nerves, hair follicles, and skin glands
37
Q
label the diagram
A
- papillary region
- reticular region
- sebaceous gland
38
Q
Label the image and give function of each
A
- Sebaceous: creates oily secretions
- Apocrine: sweat glands that create odour (present in armpits, groin)
- eccrine: open on surface of skin and leave watery sweat (controlled by ANS)
39
Q
Arrector pili muscle
A
-at base of hair follicle which makes hair stand up
40
Q
ceruminous gland
A
produces waxy substance (auditory canal)
41
Q
Skin and temperature regulation
A
- BV’s dilate to lose heat or constrict to conserve heat
- heat loss also promoted by sweat production
42
Q
Skin and blood reservoir
A
-dermis carries 8-10% of total blood volume
43
Q
Skin and protection from environment
A
- chemical: sebum containing defensins, low pH sweat helps retard the growth of microbes
- physical: continuity (no breaks), designed to withstand abrasion (thickness and keratin)
- biological: intraepidermal macrophages provide immune surveillance and help activate other immune cells
44
Q
Skin and cutaneous sensations
A
- conveys external sensations to the spinal cord
- pain, temperature, touch, pressure
45
Q
Skin and excretion & absorption
A
- waste products such as ammonia and urea excreted with sweat
- water loss
- absorbs lipids, gases, and organic solvents
46
Q
Skin and metabolism
A
- contributes to synthesis of vitamin D (calcium homeostasis)
- synthesis of vitamin D precursor requires UV exposure which is further metabolized by the liver and kidney
47
Q
Hemostasis
A
- occurs right after injury
- epinephrine (constricts peripheral blood vessels) released in an attempt to minimize bleeding into soft tissues
- platelet causes body to form a clot
- increased aggregation of platelets to complete clotting process
- platelets release cytokines which participate in later phases of healing
- objective of this phase is to control bleeding
48
Q
Inflammatory phase of wound healing
A
- symptoms: swelling, increased fluid, profusion of blood, redness, release of epinephrine/histamine, heat, pain
- macrophage, neutrophils, and leukocytes destroy bacteria
- macrophages create cytokines and growth factors which act as chemoattractants to other cells needed for tissue repair
- macromolecules converted into amino acids needed for wound healing
- contractual cells also released
49
Q
Proliferation phase of wound healing
A
- scar tissue formation characterized by 3 phases: granulation, contraction, epithelialization
- granulation: open wound produces red tissue with granular appearane that consists of fibroblasts, capillaries, and neutrophils
- contraction: as wound site accumulates with granulation it contracts
- epithelialization: cells migrate from the wound margins and ultimately touch one another sealing the wound (can only occur in the presence of viable vascular tissue)
50
Q
Maturation phase of wound healing
A
- collagen fibres reorganize and mature gaining tensal strength
- scar becomes less cellular and gains tensal strength
- this area will always be at risk for tensal breakdown because it is less tensal than other skin
- collagen synthesis begins with fibroblast secreting procollagen (platelet and macrophage are key growth factors for procollagen)
- procollagen mature into collagen fibril which then make strong network of collagen fibre
51
Q
What type of epithelial tissue is this?
A
-simple cuboidal
52
Q
What type of epithelial tissue is this?
A
-stratified squamous
53
Q
What type of epithelial tissue is this?
A
-pseudostratified ciliated columnar
54
Q
Loose connective tissue
A
- contains many cells, loose arrangement of fibres, moderately viscous fluid matrix
- generally connects and supports various tissues and organs
1. Areolar: simplest and most widely distributed. Fibres are loosely arranged and have spaces between them. Found in continous layers beneath the skin, space between many organs, between muscles, peritoneum, and mesentries.
2. Adipose: Modified form of areolar that contains many fat cells. Adipocyte has large fat droplet which shifts nucleus to periphery of cell. Found beneath skin in dermis, mesentries (connects organs to back abdominal wall), around kidney, heart and eyeballs
3. Reticular: Modified areolar tissue that contains large number of stellate shape reticular cells floating in fluid matrix. Reticular cells has number of cytoplasmic processes which are interconnected to form reticular network. Found in lymph glands, spleen, liver, bone marrow, thymus, and tonsils.
55
Q
Dense connective tissue
A
- fibres dominate over the cells and matrix in quantity
1. Regular: Fibres are parallel to each other enhancing tensile strength and resistance to stretching in the direction of the fibre orientations. Ligaments and tendons are made of this.
2. Irregular: Direction of fibres is random. Gives tissue greater strength in all directions and less strength in one particular direction. Some fibres criss cross to form a mesh or sometimes layers going in the same way are stacked at an angle. Dermis is an example rich in collagen fibres. Dense irregular elastic tissue gives arterial walls the strength and ability to regain original shape after stretching.
3. Elastic: Contains numerous elastic fibres in addition to collagen fibres which allows the tissue to return to its original length after stretching. Lungs and arteries have layer that allows the stretch and recoil of these organs.
