LEC 5

Question 1

what are viruses

Answer 1

non living particles

Question 2

why are viruses considered non living

Answer 2

cannot reproduce outside of eukaryotic cell

Question 3

STRUCTURE OF VIRUS what is located in middle of virus

Answer 3

genome

Question 4

STRUCTURE OF VIRUS what surrounds genome

Answer 4

capsid (protein)

Question 5

STRUCTURE OF VIRUS what can coat virus

Answer 5

lipid envelope

Question 6

STRUCTURE OF VIRUS what can be inserted into lipid envelope

Answer 6

glycoproteins

Question 7

STRUCTURE OF VIRUS what is the function of glycoproteins

Answer 7

allow virus to attach to host cell

Question 8

STRUCTURE OF VIRUS how does enveloped virus differ from naked virus

Answer 8

• enveloped easier to inactivate using disinfectants / alcohol
• naked harder to inactivate using disinfectants / alcohol

Question 9

what is host range of virus

Answer 9

specific

Question 10

what is bacteriophage

Answer 10

virus that infects bacteria

Question 11

how do viruses infect bacteria

Answer 11

transfer viral genome to bacteria

Question 12

what can viral genes passed on by bacteriophage encode for

Answer 12

virulence factors that cause bacteria to become disease causing

Question 13

what is characteristic of RNA virus

Answer 13

mutate quickly

Question 14

what are 6 events of viral infection

Answer 14

1. virus attaches to host cell
2. virus penetrates host cell
3. replication of genome
4. production of protein
5. assemble new virus
6. release new virus

Question 15

what are 2 methods of penetration

Answer 15

1. fusion

2. pinocytosis

Question 16

what viruses penetrate by fusion

Answer 16

enveloped

Question 17

what happens during fusion

Answer 17

lipid envelope fuses w PM

Question 18

what viruses penetrate by pinocytosis

Answer 18

naked

Question 19

what allows naked viruses to attach to host

Answer 19

capsid

Question 20

what does pinocytosis involve

Answer 20

vacuole

Question 21

what is central dogma

Answer 21

• DNA to mRNA by transcription

- mRNA to protein by translation

Question 22

how does DNA virus make viral DNA in host

Answer 22

hijack eukaryotic cell DNA polymerase

Question 23

how does RNA virus make viral RNA in host

Answer 23

viral RNA dependent RNA polymerase

Question 24

how are viral proteins made if infected by DNA virus

Answer 24

1. viral DNA transcribed to mRNA

2. mRNA translated to viral protein

Question 25

how are viral proteins made if infected by RNA virus with pos sense

Answer 25

1. pos RNA translated to viral protein

Question 26

what does pos RNA act as

Answer 26

mRNA

Question 27

how are viral proteins made if infected by RNA virus with neg sense

Answer 27

1. neg RNA transcribed to pos RNA | 2. pos RNA translated to viral protein

Question 28

what is responsible for transcription from neg RNA to pos RNA

Answer 28

viral RNA dependent RNA polymerase

Question 29

how are viral proteins produced if infected by retrovirus

Answer 29

1. RNA reverse transcribed to DNA 2. DNA transcribed to mRNA 3. mRNA translated to protein

Question 30

what is responsible for reverse transcription

Answer 30

viral RNA dependent DNA polymerase

Question 31

what happens after replication of genome + production of protein

Answer 31

genome + protein asscoiate

Question 32

what are 3 possible outcomes of viral infection

Answer 32

1. acute 2. latent 3. chronic

Question 33

what happens in acute

Answer 33

1. virus replicates | 2. cell lyse

Question 34

what does cell lysing allow (acute)

Answer 34

viruses can leave host

Question 35

what happens in latent

Answer 35

1. virus does not replicate

Question 36

what happens in chronic

Answer 36

1. virus replicates | 2. cell does not lyse

Question 37

CHICKEN POX what virus causes chicken pox

Answer 37

human herpes virus 3

Question 38

ACUTE what are symptoms of chickenpox

Answer 38

1. fever | 2. rash / lesions

Question 39

ACUTE where is virus present

Answer 39

rash / lesions

Question 40

ACUTE what is mode of transmission

Answer 40

airborne

Question 41

ACUTE what stages do do lesions exist in

Answer 41

diff stages of develoopment

Question 42

ACUTE what happens when lesions heal

Answer 42

1. virus travels up nerve innervating skin | 2. virus settles in dorsal root ganglion +remains dormant

Question 43

SHINGLES what causes shingles

Answer 43

hhv3 reactivation from latent phase

Question 44

SHINGLES how does chickenpox differ from shingles

Answer 44

- chicken pox ==> itchy | - shingles ==> itchy + painful

Question 45

what are complications of CP

Answer 45

1. secondary bacterial infections 2. CNS infections a. meningitis (CSF) b. encephalitis (brain tissue) c. myelitis (nerves)

Question 46

SHINGLES what is complication of shingles

Answer 46

post hepatic neuralgia

Question 47

SHINGLES what is neuralgia

Answer 47

nerve pain

Question 48

what is hh3 antiviral

Answer 48

acylovir

Question 49

what is active immunization

Answer 49

live attenuated virus

Question 50

what is live attenuated virus

Answer 50

virus that is changed so as not to cause disease

Question 51

what is passive immunization

Answer 51

antibody to virus

Question 52

what is the diff bw small pox and chicken pox

Answer 52

- small pox ==> lesions are at same stage of development | - chicken pox ==> lesions are at diff stage of development

Question 53

ONCOGENIC VIRUS how do oncogenic viruses work

Answer 53

turn host cell to cancerous cell

Question 54

ONCOGENIC VIRUS what kind of viruses are oncogenic viruses (2)

Answer 54

1. DNA virus | 2. RNA virus

Question 55

what are 2 ways of diagnosing virus

Answer 55

1. culture | 2. PCR

Question 56

what happens in PCR

Answer 56

detect genome of virus

Question 57

what is cytopathic effect (CPE)

Answer 57

- cyto ==> cell | - pathic ==> disease

Question 58

what is syncytia

Answer 58

CPE where virus combines cells surrounding host to form large virus producing factory

Question 59

PRIONS what are prions

Answer 59

mis folded proteins

Question 60

PRIONS what happens when proteins become unfolded

Answer 60

lose function