U4A1: 7A DETECTING PATHOGENS

Question 1

define pathogen

Answer 1

an agent that causes disease

Question 2

define antigen

Answer 2

molecule that may trigger an immune response

Question 3

define self-antigen

Answer 3

mark the cells of an organism as ‘self’ so that the immune system doesn’t attack them.

Question 4

2 classes of self-antigens

Answer 4

MHC 1, on all nucleated body cells
MHC 2, on specialised immune system cells

Question 5

define non-self antigen

Answer 5

antigens the immune system reads as ‘foreign’. the immune system activates and destroys.

Question 6

2 common antigen malfunctions

Answer 6

autoimmune disease, where the immune system recognises self cells as non-self cells
allergies, where the immune system overreacts to allergens (harmless non-self antigen)

Question 7

how do red blood cells label themself as ‘self’ cells?

Answer 7

they don’t have MHC proteins, instead they use different glycoproteins to distinguish between blood types.

Question 8

define cellular pathogens

Answer 8

have a cellular structure and are living organisms

Question 9

4 types of cellular pathogens

Answer 9

bacteria
fungi
worms
protozoas

Question 10

examples of bacteria

Answer 10

meningitis, tetanus

Question 11

examples of fungi

Answer 11

thrush, tinea

Question 12

examples of worms

Answer 12

tapeworm, roundworm

Question 13

examples of protozoas

Answer 13

malaria

Question 14

define non-cellular pathogens

Answer 14

do not have a cellular structure and are non-living.

Question 15

2 types of non-cellular pathogens

Answer 15

viruses
prions

Question 16

examples of viruses

Answer 16

influenza, COVID-19

Question 17

examples of prions

Answer 17

mad cow disease