Principles

Question 1

Do gram negative organisms release endotoxins or exotoxins?

Answer 1

endotoxins

Question 2

Do gram negative organisms have a thick or thin layer of peptidoglycan?

Answer 2

thin

Question 3

Regarding Staph aureus, which part of the name is the genus and which is the species?

Answer 3

staph = genus, aureus = species name

Question 4

Are streptococci in chains or clusters?

Answer 4

chains

Question 5

Are staphylococci in chains or clusters?

Answer 5

clusters

Question 6

Do prion proteins contain DNA or RNA?

Answer 6

neither

Question 7

What do prion proteins cause?

Answer 7

TSEs (prion diseases) such as Mad Cow Disease

Question 8

What are viruses made of?

Answer 8

RNA or DNA with a protein coat

Question 9

How are viruses diagnosed?

Answer 9

cell culture, serology and PCR

Question 10

How can bacteria be seen?

Answer 10

light microscopy

Question 11

What are bacter made of?

Answer 11

DNA and RNA and consist of one double stranded chromosome

Question 12

How does bacteria replicate?

Answer 12

By binary fission about every 20 minutes

Question 13

What are examples of organisms which do not stain well?

Answer 13

TB and treponema pallidum

Question 14

What is an opportunistic pathogen?

Answer 14

causes infection in immunocompromised individual

Question 15

What is commensal bacteria part of?

Answer 15

the normal flora

Question 16

What is virulence?

Answer 16

how easily a pathogen can cause disease

Question 17

What is a microaerophilic atmosphere?

Answer 17

one reduced in oxygen but enriched in C02

Question 18

What can toxins cause the release of?

Answer 18

cytokines

Question 19

What can toxins damage?

Answer 19

red and white blood cells (can lead to sepsis)

Question 20

What can C.D and Bacillus sp. form?

Answer 20

spores

Question 21

Who was Anthrax (bacillus anthracis) common in and where did it come from?

Answer 21

heroin users, animal skin

Question 22

How long does a TB culture take?

Answer 22

4-12 weeks

Question 23

How long does an agar culture take?

Answer 23

48 hours

Question 24

What do moulds produce?

Answer 24

hyphae, meaning they invade organic tissue

Question 25

What are yeast cells?

Answer 25

single cells, reproduce by budding

Question 26

What is the most common cause of yeast infection?

Answer 26

candida spp.

Question 27

What is the most common mould infection?

Answer 27

aspergillus spp.

Question 28

What genus is the only one for which haemolysis is important for classification?

Answer 28

steptococci

Question 29

What does alpha haemolysis mean?

Answer 29

partial haemolysis, causes greenish discolouration around the colony

Question 30

What is beta-haemolysis?

Answer 30

complete haemolysis, causes complete clearing around the colony

Question 31

What is gamma-haemolysis?

Answer 31

no haemolysis e.g. enterococci

Question 32

What type of haemolysis occurs in most pathogenic streptococci?

Answer 32

beta

Question 33

What type of Strep is the most pathogenic of all strep?

Answer 33

Group A

Question 34

What test distinguishes staph aureus from all other staphylocci?

Answer 34

coagulase

Question 35

What can treat staph aureus?

Answer 35

flucloxacillin

Question 36

What are large gram negative bacilli that look like E.coli called?

Answer 36

coliforms

Question 37

What is the first line antibiotic used to treat infections caused by coliforms?

Answer 37

gentamycin

Question 38

What is the first line treatment for infections caused by anaerobes?

Answer 38

metronidazole

Question 39

What causes Lyme's disease?

Answer 39

Borrelia burgdorferi