6.2 + 6.3

Question 1

what are endotoxins?

Answer 1

• gram negative!! - have lipolysaccharide layer
• lipid part acts as toxin - released when bacterium disintegrates

Question 2

example of endotoxin

Answer 2

salmonella spp

Question 3

best way to treat salmonella

Answer 3

avoid it!! - avoid contact w contaminated ppl - their food/water, kitchen + personal hygiene, contact w uncooked meat + other food, cook properly, vaccinate chickens

Question 4

what r exotoxins

Answer 4

both gram pos + gram neg
- soluble proteins (toxins) produced + released into body by bacteria
- can disrupt cell membranes -> cell death/internal bleeding etc

Question 5

example of exotoxin

Answer 5

staphylococcus spp.

Question 6

how does one get staphylococcus spp?

Answer 6

• when staphylococci on skin enters tissues via cut or if person has compromised immune system and in contact w infected individual

Question 7

are ABs effective against staph

Answer 7

yes if prompt diagnosis, some strains like MRSA r resistant to ABs though

Question 8

what are three ways pathogenic effects can be produced by bacteria

Answer 8

1. exotoxins
2. endotoxins
3. invasion of host tissue

Question 9

example of bacteria that does invasion of host tissue

Answer 9

mycobacterium tuberculosis

Question 10

what does mycobacterium TC affect

Answer 10

• lungs - respiratiry systen
• also suppresses immune system
• this bacterium produces a thick waxy outer layer to protect it from enzymes of macrophages

Question 11

how do bacteriostatic ABs work

Answer 11

Prevents reproduction by affecting dna replication

Question 12

eg of bacteriostatic AB

Answer 12

tetracycline - prevents protein synthesis - no bacterial reproduction as no proteins/enzymes made

Question 13

how do bactericidal ABs work

Answer 13

• kills bacteria by affecting structure of cell membrane/wall - kills almost all pathogens present - any remaining can be destroyed by immune system

Question 14

eg of bactericidal AB

Answer 14

penicillin