inflammation & wound healing

Question 1

function of the skin

Answer 1

• protects us from microbes and the elements
• helps regulate body temperature
• facilitates the sensations of touch, heat and cold

Question 2

3 layers of the skin

Answer 2

epidermis, dermis, hypodermis

Question 3

epidermis

Answer 3

outermost layer of skin, provides a waterproof barrier and creates our skin tone

Question 4

dermis

Answer 4

mid layer, contains tough connective tissue, hair follicles and sweat glands

Question 5

hypodermis

Answer 5

subcutaneous tissue which is made of fat and connective tissue

Question 6

stratum corneum

Answer 6

ontop of the tree living layers; made up of dead flattened epidermal cells which is made up of keratin

Question 7

components of the skin

Answer 7

blood vessels, sebaceous glands, sweat glands, colour, hair follicle

Question 8

function of blood vessels in the skin

Answer 8

help maintain body temperature, dilate in heat, constrict in response to cold

Question 9

function of sebaceous glands in the skin

Answer 9

secrete sebum, helps keep skin from drying out- located in the base of hair follicles

Question 10

function of sweat glands in the skin

Answer 10

evaporates heat in aid to cool you, located mainly in the palm of your hands and in your forehead

Question 11

function of the colour of the skin

Answer 11

produced by cells called melanocytes which produce the pigment melanin, which are located in the epidermis

Question 12

4 stages of wound healing

Answer 12

haemostasis, inflammation, proliferation, remodelling

Question 13

process of haemostats

Answer 13

• vasoconstriction occurs, limiting blood flow to the injured site
• platelets stick to the site of injury, which closes up, controlling the bleeding
• stabilised by a protein called fibrin, which forms a mesh with the platelets and creates a clot

Question 14

process of inflammation

Answer 14

• capillaries dilate to allow more fluid to the injured site
• pyrogens are release to increase temperature
• pain receptors become activated
• phagocytes migrate to the site of injury

Question 15

purposes of acute inflammation

Answer 15

• limits spread of injury
• dilutes or removes harmful agents
• removes damaged cells

Question 16

5 cardinal signs of inflammation

Answer 16

pain, heat, redness, swelling, loss of function (only mobile)

Question 17

2 components to inflammation

Answer 17

vascular and cellular phase

Question 18

vascular phase

Answer 18

stimulated by the presence of cytokines

Question 19

what signalling molecules are released in the presence of damaged tissue?

Answer 19

• mast cells which burst releasing histamine, bradykinin and serotonin
• prostaglandins
• platelets

Question 20

pain is caused by the release of

Answer 20

bradykinin and prostaglandins

Question 21

redness and heat is caused by the release of

Answer 21

histamine/ serotonin

Question 22

process of vascular stage of inflammation

Answer 22

• changes to the capillary bed at the site of injury
• this increases blood flow and permeability
• chemical signals are released to get a response from the immune system

Question 23

cellular stage of inflammation

Answer 23

arrival of white blood cells

Question 24

function of neutrophils

Answer 24

destroy bacteria

Question 25

function of macrophages

Answer 25

destroy bacteria, clean up cellular debris, signal for proliferation to start

Question 26

processes of the cellular phase of inflammation

Answer 26

margination, rolling, adhesion, transmigration, chemotaxis

Question 27

margination

Answer 27

as blood flow becomes slower, phagocytes drop to the margins

Question 28

pavementing

Answer 28

weak attraction and rolling along the endothelial surface

Question 29

adhesion

Answer 29

phagocyte attaches strongly to attachment proteins

Question 30

transmigration

Answer 30

phagocyte ‘squeezes’ through permeable endothelial membrane into intracellular spaces

Question 31

chemotaxis

Answer 31

phagocytes move to area of damage

Question 32

function of macrophages

Answer 32

• continue the release of cytokines, to attract mote macrophages and fibroblasts
• release growth factors
• release anti-inflammatory mediators

Question 33

proliferation

Answer 33

• wound is rebuilt with new ‘granulation tissue’
• wounds contract due to myofibroblasts which grip the wound edges and pull them together
• angiogenesis occurs

Question 34

angiogenesis

Answer 34

new network of blood vessels are developed

Question 35

by the end of proliferation

Answer 35

• epithelial cells have re-covered the site
• blood vessels have invaded new tissue
• fibroblasts have filled the wound site
• macrophages remain

Question 36

process of remodelling

Answer 36

• collagen is laid down
• water is reabsorbed so the collagen fibres lie closer together
• cells that have been used to repair the wound that are no longer needed are removed
• this new skin has only 80% of the tensile strength of the unwounded skin

Question 37

function of myfibroblasts in remodelling

Answer 37

move over the collagen bundles, attach and contract reducing its size, which reduces the size of the scar tissue

Question 38

apoptosis

Answer 38

the process of normal cell death