microbiology revision

Question 1

complement system leads to

Answer 1

phagocytosis of c3b coated bacteria
inflammation
lysis of microbe

Question 2

stages of sample processing bacteriology

Answer 2

sample
plate onto enrichment media
pick off colonies
plate onto selective/differential agars
pick off colonies
gram stain
definitive ID

Question 3

catalase test

Answer 3

positive for staphylococcus
negative for streptococcus

Question 4

following a positive catalase test which test would you do

Answer 4

coagulase

Question 5

coagulase test

Answer 5

positive staph aureus

Question 6

following negative coagulase test which test

Answer 6

novobiocin sensitivity

Question 7

positive novobiocin test

Answer 7

staph epidermis

Question 8

negative novobiocin test

Answer 8

staph saprophyticus

Question 9

following negative catalase test which test

Answer 9

hemolysis

Question 10

testing for strep pneumoniae

Answer 10

negative catalase
alpha hemolysis positive

Question 11

testing for s pyogenes

Answer 11

negative catalase
beta hemolysis positive

Question 12

testing for s agalactiae

Answer 12

negative catalase
beta hemolysis negative

Question 13

why do we want to identify pathogens

Answer 13

improved treatment and outcomes
more appropriate use of antibiotics
managing outbreaks

Question 14

what are many class 3 reactions for

Answer 14

selective toxicity

Question 15

antibacterial drug for cell wall synthesis

Answer 15

cephalosporins

Question 16

antibacterial drug for cell wall integrity

Answer 16

beta lactamases

Question 17

antibacterial drug for DNA synthesis

Answer 17

metronidazole

Question 18

antibacterial drug for DNA gyros

Answer 18

quinolones

Question 19

antibacterial drug for RNA polymerase

Answer 19

rifampicin

Question 20

antibacterial drug for phospholipid membrane

Answer 20

polymyxins

Question 21

antibacterial drug for protein synthesis, 30S inhibitors

Answer 21

tetracyclins

Question 22

antibacterial drug for protein synthesis, 50S inhibitors

Answer 22

clindamycin

Question 23

drugs that may overcome resistance

Answer 23

co amoxiclav

Question 24

antiviral drugs targeting attachment and entry inhibitors

Answer 24

maraviroc

Question 25

antiviral drugs targeting ion channel blockers

Answer 25

rimantadine

Question 26

antiviral drugs targeting polymerase inhibitors

Answer 26

acyclovir

Question 27

antiviral drugs targeting integrase inhibitors

Answer 27

raltegravir

Question 28

antiviral drugs targeting protease inhibitors

Answer 28

ritonavir

Question 29

antiviral drugs targeting neuraminidase inhibitors

Answer 29

oseltamivir

Question 30

infectious disease control

Answer 30

environment behaviour change antimicrobial agents vaccination public health awareness surveillance infection control measures

Question 31

factors in viral pathogenesis

Answer 31

effects of viral infection on cells entry into host course of infection cell tropism cell damage host immune response virus clearance or persistence

Question 32

how can cells respond to viral infections

Answer 32

no change death transformation

Question 33

direct cell damage from viral infection may result from

Answer 33

diversion of cells energy shut off of cell macromolecular synthesis competition of viral mRNA for cellular ribosomes competition of viral promotors and transcriptional nhances

Question 34

indirect cell damage can result from

Answer 34

integration of viral genome induction of mutations in host genome inflammation host immune response

Question 35

COVID-19 replication

Answer 35

spike protein binds to ACE2 receptors TMPRSS2 and cathepsin cleaves S glycoprotein enables cell membrane viral fusion and viral RNA release may create a pore so viral RNA can enter or may be internalised by endocytosis and uncoated in lysosomal environment which would release ssRNA into cytosol viral genome replicated and translated into viral proteins envelope glycoproteins and process in Golgi released by vesicular exocytosis

Question 36

what is the influenza a virus

Answer 36

enveloped negative sense ssRNA

Question 37

influenza viral replication

Answer 37

virus adsorbs to respiratory epithelium by hem agglutinin spikes fuses with the membrane virus is endocytose into vacuole releases 8 nucleocapsid segments into cytoplasm nucleocapsids transported to nucleus negative sense ran is transcribed t positive sense translated into viral proteins positive sense rna synthesises glycoprotein spikes inserted into the host membrane positive sense rna synthesises new negative sense, assembled into nucleocapsids transported out of nucleus to cell membrane release of mature virus, budded off with spiked envelope

Question 38

how would strep pyogenes be identified in the lab

Answer 38

sputum sample taken cultured on general medium, blood agar look for beta haemolytic colonies pick off colonies make smear on slide gram stain look for gram positive cocci chains definitive ID based on API or MALDI

Question 39

alpha hemolysis

Answer 39

partial hemolysis green

Question 40

beta hemolysis

Answer 40

complete hemoylsis clear