Disease C7

Question 1

Pathogen

Answer 1

Disease causing organisms

Question 2

Hosts

Answer 2

Organism infected by a pathogen

Question 3

Disease

Answer 3

Any condition that interferes with how an organism or any part of in functions

Question 4

Examples of cellular pathogens

Answer 4

Parasites, protozoa, fungi, prokaryotes

Question 5

Examples of acellular pathogens

Answer 5

Viruses and prions

Question 6

Genetic diseases

Answer 6

Due to mutations inherited from parents (cystic fibrosis)

Question 7

Autoimmune diseases

Answer 7

Immune system attacks own body - can’t detect the difference between self and non self (Arthritis)

Question 8

Susceptibility

Answer 8

Level of response by an organism to a pathogen

Question 9

Resistance

Answer 9

Extent to which an organism is not affected by an agent

Question 10

Pathogenicity

Answer 10

Disease causing capacity of a pathogen

Question 11

Virulence

Answer 11

The intensity of pathogen’s effect

Question 12

3 Phases of disease

Answer 12

1. Infection (pathogen entry)
2. Incubation (person is asymptomatic but infectious)
3. Symptoms evident (usually from immune response)

Question 13

Methods of transmission

Answer 13

Inhaled droplets (flu)
Direct contact (Herpes)
Bodily fluids (HIV)
Animal vectors (Rabies)
Blood Contact (Hep B)
Ingested (Salmonella)
Also via fomite transmission (on objects like door handles)

Question 14

Virus structure, example and reproduction method

Answer 14

Genetic material, protein coat ( and sometimes lipid envelope)
Sars CoV 2
Lytic cycle (invade, take over host cell machinery, burst or bud out)

Question 15

What is the R0 number?

Answer 15

Basic reproduction no. in epidemiology - how many people could one person infect?

Question 16

What do antibiotics do?

Answer 16

Target specific metabolic pathways in bacteria - can’t on viruses, as not made of the same things (cell membrane vs lipid or protein coat)

Question 17

Why should antibiotics be dispensed with care?

Answer 17

Bacteria can evolve to be resistant to the antibiotic, meaning that, if spread, the antibiotic may not work at all against the new strain

Question 18

Fungi structure, example and reproduction

Answer 18

Cell wall (eukaryotic), ringworm, can be sexual or asexual

Question 19

Parasite structure, example and reproduction

Answer 19

can be prokaryotes (worms, ticks etc - ecto and endo parasites) or eukaryotes (protists) and can have flagella, can reproduce sexually or asexually

Question 20

Bacteria structure, example and reproduction

Answer 20

prokaryotic cell, staph, aesexual

Question 21

Prion structure, example and reproduction

Answer 21

Just a misfolded PrP protein, Mad Cow Disease and touch normal PrP and cause them to change shape

Question 22

Define immune

Answer 22

Have antibodies

Question 23

Define herd immunity

Answer 23

Most of population vaccinated so disease is less transmissible to those who are not vaccinated

Question 24

Define natural passive immunity

Answer 24

Breastmilk - no antibodies made

Question 25

Define natural active immunity

Answer 25

Normal infection and immune response

Question 26

Define artificial passive immunity

Answer 26

Antivenom for snake bite - artificial and no antibodies made

Question 27

Define artificial active immunity

Answer 27

Vaccination

Question 28

List 1st line mechanical barriers

Answer 28

Skin, ciliated membranes, non - pathogenic bacteria, earwax

Question 29

List 1st line chemical barriers

Answer 29

Mucus, saliva, sweat, lysosomes, acidic pH, stomach acid

Question 30

What is the 1st line of defence?

Answer 30

Non - specific, non - adaptive, works from day 1

Question 31

List 2nd line of defence cells and function

Answer 31

Phagocytes (Macrophages, APC cells, Neutrophils) Granulocytes (Mast cells, basophils, eosinophils, neutrophils, NK cells)

Question 32

How does immune system know self from non self?

Answer 32

MHC

Question 33

Name 2nd line processes and function

Answer 33

Fever: increase rate of mitosis of self cells, push pathogens out of optimum range, make antibodies and cytokines faster, cellular respiration faster Too high can denature self enzymes Inflammation: Mast cells (on direct antigen contact) release histamine, makes BV more permeable and Vasodilation = hot, sore, swollen Blood clotting via platelets: platelets activated, fibrin made, sticks blood cells to the clot, making it bigger The complement - more detail in other cards

Question 34

What is the complement and how does it work?

Answer 34

Activated by antibodies, 20 proteins, normally inactive, can do MAC, opsonization and neutralization

Question 35

What cells are in the 3rd line?

Answer 35

B Cells (plasma, memory) and T cells (helper, killer, repressor, memory)

Question 36

What is cell mediated immunity?

Answer 36

Done by T cells, cells are directly combating pathogen

Question 37

What is humoral mediated immunity?

Answer 37

B cells, create antibodies that bind to pathogen, indirect combat

Question 38

What is clonal selection?

Answer 38

T cell is clonally selected when APC cell shows it the antigen it is specific for (clones itself into 4 types of T cell)

Question 39

4 Antibody functions

Answer 39

Opsonisation, Neutralisation, Agglutination, Activating the complement