Microbiology

Question 1

What components make up an organisms name?

Answer 1

genus and species name

Question 2

what are prion proteins?

Answer 2

infectious proteins with no DNA or RNA

Question 3

what are viruses?

Answer 3

obligate intracellular parasites

Question 4

how can viruses be diagnosed?

Answer 4

antigen/antibody direction in blood

PCR

Question 5

structural components of bacteria

Answer 5

one double stranded chromosome
cell membrane, cell wall and sometimes capsule
flagellae
pili

Question 6

3 shapes of bacteria

Answer 6

coccus
bacillus
spirochaetes

Question 7

gram positive?

Answer 7

purple

Question 8

gram negative?

Answer 8

pink

Question 9

how do bacteria replicate?

Answer 9

binary fission

Question 10

3 types of atmosphere bacteria grow in?

Answer 10

1. aerobic
2. microaerophillic
   grow in an atmosphere enriched with CO2
3. anaerobic
   no oxygen present in atmosphere

Question 11

what produces exotoxin?

Answer 11

gram positive

produced in cell and exported out

Question 12

what produces endotoxin?

Answer 12

gram negative

part of cell wall

Question 13

what produces spores?

Answer 13

gram positive bacilli, e.g C diff and Bacillus

Question 14

how can bacteria be diagnosed?

Answer 14

• microscopy
• culture
• antigen detection
• antibody detection (serology)
• PCR

Question 15

what are moulds?

Answer 15

a type of fungo

produce spores and hyphae

Question 16

what is yeast?

Answer 16

a type of fungi, reproduces by budding

Question 17

what bacteria are differentiated by haemolysis?

Answer 17

streptococcus

Question 18

what are the 3 types of haemolysis?

Answer 18

1. alpha, partial
2. beta, complete
3. gamma, none

Question 19

what undergoes partial haemolysis?

Answer 19

strep pneumoniae

strep viridans

Question 20

what undergoes beta haemolysis?

Answer 20

group A and B strep

Question 21

what does not undergo haemolysis?

Answer 21

enterococci

Question 22

coagulase positive staph?

Answer 22

staph aureus

Question 23

coagulase negative staph?

Answer 23

staph epidermis etc (skin commensals)

Question 24

steps of fever

Answer 24

1. antigen/endotoxin interact with macrophages
2. macrophages release cytokines into the bloodstream
3. cytokines travel to anterior hypothalamus
4. prostaglandin E is released (increases bodys thermal set point)
5. FEVER

Question 25

sepsis

Answer 25

- small blood vessels become leaky and lose fluid into the tissues - increased HR, as must work harder to oxygenate tissues - blood supply to less essential organs is shut down - blood clotting system is activated, causing blood clotting in tiny vessels (to stop uneeded perfusion)

Question 26

what are coliforms?

Answer 26

gram negative bacilli that look like e.coli on gram film, cause infection when in a sterile site

Question 27

antibiotic to treat coliforms?

Answer 27

gentamicin

Question 28

antibiotic to treat infections caused by anaerobes?

Answer 28

metronidazole

Question 29

steps of gene transfer in bacteria

Answer 29

1. transformation DNA of dead can be taken up by living 2. conjugation bacterial sex, by which plasmids can be transferred 3. transduction viruses that infect bacteria can transfer bacteria between two

Question 30

4 mechanisms of resistance

Answer 30

1. production of enzymes that destroy antibiotics 2. altered antibiotic binding sites 3. alteration of cell wall porins 4. up regulation of efflux pumps

Question 31

what is beta lactamase resistant to?

Answer 31

penicillins e.g amoxicillin

Question 32

ESBL resistant to?

Answer 32

penicillins and cephalosporins

Question 33

CPE resistant to? (carbapenemase)

Answer 33

penicillins, cephalosporins and carbapenems