Non Specific Immune Defense

Question 1

Blood clotting

Answer 1

1) when platelets come in contact with collagen they begin secreting substances
2) substances include thrombostin: enzyme that triggers cascade of reactions resulting in blood clot formation
- serotonin: makes smooth muscle contract, reducing blood flow- vasoconstriction

Question 2

Inflammatory

Answer 2

-mast cells activated releasing chemicals like histamines and cytokines
- histamines causes vasodilation causing localised heat and redness. Raised temperature prevents pathogens from reproducing
- cytokines attract WBC and dispose of pathogens by phagocytosis

Question 3

Fevers

Answer 3

• thermogenic point in body increases to kill any pathogens as they reproduce below 37
• immune system works better at higher temperatures

Question 4

Phagocytosis

Answer 4

1) pathogens produce chemicals that attract phagocytes

2) phagocytes recognise them as foreign and engulfs pathogen in a phagosome

3) phagosome combines with lysosome to form phagolysosome

4) enzymes from lysosome digest and destroy pathogen

5) digested pathogen is absorbed by phagocyte antigen combined with MHC

6) mhc/antigen complex displayed on membrane making antigen presenting cell

Question 5

What are opsonins

Answer 5

• molecules that bind to pathogens and foreign particles making them more recognised and are consumed by phagocytosis or example antibodies binding to pathogens

Question 6

What are agglutinins

Answer 6

• substances that cause foreign particles to clump together making it more clear they are pathogens for example antibodies

Question 7

What are antitoxins

Answer 7

• substances that are produced by immune system to neutralise harmful toxin effects