Non-specific diseases

Question 1

What are non-specific defences?

Answer 1

these responses are exactly the same no matter what type of species of the invading pathogens

Question 2

What are specific defences?

Answer 2

• these responses produce antibodies and cytotoxic cells specific to invading pathogens

Question 3

How does the skin act as an non-specific defence?

Answer 3

• Flora of healthy microorganisms that out compete pathogens for space
• sebum (oils) - inhibits growth of pathogens

Question 4

How does the mucous membranes act as an non-specific defence?

Answer 4

• Body tracts e.g air ways in the vagina lined by the mucus membranes
• mucus traps microorganisms
• lysosomes destroy pathogen cell walls
• phagocytes engulfs pathogens

Question 5

How does the inflammatory response act as an non-specific defence?

Answer 5

• It is a localised response resulting to the inflammation at the site of a wound.
• Characterised by pain, heat
• mass cells are activated in damaged tissue and releases chemicals
• Histamines make blood vessels dilate, causing heat and redness which prevents pathogens from entering.

Question 6

How does blood clotting and wound repair act as an non-specific defence?

Answer 6

• plateletes become sticky
• they block hole/wound
• Fibrin fibres clump the plateles and trap red blood cells together
• thromboplastin - an enzyme that triggers a Cascades of reactions resulting in the formation of a blood clot
• serotonin - makes smooth muscles in the walls of the blood vessels and contract so they narrow and reduce the supply to the blood area.