12.5 Non-specific defences against pathogens

Question 1

what is faster specific or non-specific defence?

Answer 1

non-specific

Question 2

examples of barriers the body has to pathogens

Answer 2

skin
membranes
organelles

Question 3

skin

Answer 3

skin produces sebum to prevent growth of pathogens

contains healthy microorganisms which outcompete the pathogenic microorganisms

Question 4

membranes

Answer 4

mucous membranes secrete mucus which traps pathogens and microorganisms
mucus contains lysosomes and phagocytes which are used ti destroy the pathogen being trapped

Question 5

organs

Answer 5

lysosomes are found in tears and urine
acid in the stomach

Question 6

describe how blood clotting occurs?

Answer 6

tissue is damaged
thromboplastin and serotonin are released
thromboplastin leads to the production of thrombin
thrombin catalyses the conversion of fibrinogen to fibrin
fibrin hardens to form a clot

Question 7

what does serotonin do?

Answer 7

causes smooth muscle in blood vessels to contract which narrows the lumen and reduces blood supply to the damaged area

Question 8

what is activated when inflammation occurs?

Answer 8

mast cells

Question 9

what do mast cells release?

Answer 9

histamines and cytokines

Question 10

role of histamines?

Answer 10

causes blood vessels to dilate which increases the temperature to prevent pathogens from reproducing

Question 11

role of cytokines?

Answer 11

attract phagocytes and allow for phagocytosis of pathogens to occur