Viruses

Question 1

Which virus causes Chickenpox?

Answer 1

Varicella Zoster Virus (VZV)

Question 2

Which virus causes Shingles?

Answer 2

Varicella Zoster Virus (VZV)

Question 3

What is Herpes Zoster another word for?

Answer 3

Shingles

Question 4

What is the active form of acyclovir?

Answer 4

Acycloguanosine triose phosphate (acyclo GTP)

Question 5

Acyclovir derives from which compound?

Answer 5

Deoxyguanosine

Question 6

Deoxyguanosine is changed to acyclovir by which chemical?

Answer 6

Thymidine Kinase

Question 7

Name x3 viruses Acyclovir can be used to treat

Answer 7

Herpes Simplex virus,
Epstein Barr virus +
Varicella Zoster virus

Question 8

What is the difference between a nucleotide and a nucleoside?

Answer 8

Nucleosides only possess a sugar and a base in their structure. There is no phosphate group.

Question 9

What is the name for the nucleoside of adenine?

Answer 9

Adenosine deoxyadenosine

Question 10

What is the name for the nucleotide of adenine?

Answer 10

Adenylate deoxyadenylate

Question 11

Define latency

Answer 11

The ability to induce life-long infection in a host cell

Question 12

What is the group name of drugs Acyclovir falls under?

Answer 12

Nucleoside analogues

Question 13

Name two mechanisms by which resistance to acyclovir can occur

Answer 13

Viral Thymidine kinase mutation

Viral DNA polymerase mutation

Question 14

What does Acyclovir do?

Answer 14

Inhibits DNA replication

Question 15

Name x3 Gram positive bacteria

Answer 15

Staphylococcus aureus, streptococcus pneumoniae and streptococcus pyogenes

Question 16

Name x3 Gram negative bacteria

Answer 16

Escheria Coli, Vibrio Cholerae and Shigella

Question 17

Name two intracellular bacteria

Answer 17

Shigella, Salmonella

Question 18

Name three extracellular bacteria

Answer 18

Streptococcus, staphylococcus and neisseria

Question 19

What are the three methods for horizontal gene transfer?

Answer 19

Conjugation, Transduction and Transformation

Question 20

What are two differences between gram positive and gram negative bacteria?

Answer 20

Gram positive bacteria stains purple whereas gram negative bacteria stains pink. Gram negative bacteria have an additional membrane with a thinner peptidoglycan layer.

Question 21

What causes the pink staining in gram negative bacteria?

Answer 21

Gram negative bacteria has a thinner peptidoglycan structure meaning that dye is lost.

Question 22

Where is staphylococcus aureus often found?

Answer 22

In the nasal cavity and skin

Question 23

Where is the streptococcus species often found?

Answer 23

In the mouth

Question 24

Where is Streptococcus group B found?

Answer 24

In the small/large intestine and genital tract

Question 25

Name x3 microbes found in the small/ large intestine

Answer 25

Escheria Coli, Candida and Streptococcus group B

Question 26

Name a commensal bacteria

Answer 26

Lactobacillus

Question 27

Name x3 points of entry for bacteria

Answer 27

1. Upper respiratory tract 2. Urogenital tract 3. Gastro-intestinal tract

Question 28

Name x2 upper respiratory tract infections

Answer 28

Tonsillitis, sinusitis

Question 29

Name x2 lower respiratory tract infections

Answer 29

Pneumonia, bronchitis

Question 30

Define Sepsis

Answer 30

Organ dysfunction in response to an infection

Question 31

Name x3 bacteria causing infection in the gastro-intestinal tract

Answer 31

Salmonella typhi, Shigella and Escheria Coli

Question 32

Name an example of an opportunistic bacteria

Answer 32

Staphylococcus epidermidis

Question 33

What is virulence?

Answer 33

Features that enhance disease causation

Question 34

Name x5 things that can affect pathogenicity

Answer 34

1. Transmission to host 2. Replication rate 3. Toxin production 4. Tropism 5. Ability to colonise

Question 35

What does a low infectious dose mean?

Answer 35

A lower average amount of bacteria are needed to cause disease e.g. Mycobacterium tuberculosis

Question 36

What bacteria causes tonsillitis?

Answer 36

Streptococcus pyogenes

Question 37

Name an infection with a high infectious dose

Answer 37

Vibrio Cholerae

Question 38

Describe a virulence mechanism by staphylococcus aureus

Answer 38

Staphylococcus aureus makes leukocidins which makes holes in host neutrophils and cause neutrophil death

Question 39

What is pus made up of?

Answer 39

Dead neutrophils

Question 40

What shape bacteria are E.coli, salmonella and shigella?

Answer 40

Gram negative Bacilli shapes (rods)

Question 41

Do opportunistic bacteria have high or low virulence?

Answer 41

Low virulence

Question 42

How does the injectisome work?

Answer 42

The injectisome allows virulence proteins to move into the cell via the translocase complex. The injectisome causes polymerisation of the actin cytoskeleton and membrane ruffling = allows bacteria in.

Question 43

What are pathogenicity islands?

Answer 43

DNA which codes for proteins contributing to virulence by making injectisomes or toxins.

Question 44

How can antibiotics be harmful to normal flora?

Answer 44

Antibiotics can kill commensal flora which usually serves as competition for pathogens. This allows pathogens to grow and produce toxins.

Question 45

What are protozoa?

Answer 45

Single celled eukaryotes.

Question 46

Are bacteria eukaryotes or prokaryotes?

Answer 46

Prokaryotes.

Question 47

Are viruses prokaryotes or eukaryotes?

Answer 47

NEITHER.

Question 48

HIV, SARS and Influenza are all examples of what?

Answer 48

Viruses; obligate and not free-living.

Question 49

x2 differences between viruses and bacteria

Answer 49

Virus = plasmid and no organelles. Bacteria = linear DNA + organelles.

Question 50

Candida albicans is under what class group?

Answer 50

Fungi