Virus Lecture 1

Question 1

What is the first animal virus?

Answer 1

foot and mouth disease 1898

Question 2

what is the first human virus?

Answer 2

yellow fever virus in 1901

Question 3

Viruses are smaller than ___, ___, & ___ ____

Answer 3

bacteria, fungus, and other microorganisms

Question 4

Virus means what in greek?

Answer 4

poison

Question 5

Vrisuses are what in nature?

Answer 5

ubiquitous

Question 6

What are the two theories of virus origin?

Answer 6

cellular and autopoietic origin

Question 7

what is cellular origin?

Answer 7

proposes that viruses were once cellular components but over time they evolved separately

Question 8

what is the autopoietic origin?

Answer 8

proproses that viruses, once autopoietic entities, became dependent on cells for replication?

Question 9

What are the 3 events of viruses in history?

Answer 9

Measles in Boston
Yellow fever in US
1918 pandemic

Question 10

what are the 5 attributes of virus clasification

Answer 10

virus particle structure
genome
replication features
serology
stability

Question 11

what are the 3 components of particle structure for viruses

Answer 11

composition
shape
size

Question 12

define nucleocapsid

Answer 12

RNA or DNA in a core that is protected by a protein coat

Question 13

Virus is defined by the ___ ___

Answer 13

nucleocapsid structure

Question 14

Nucleocapsid is comprised of repeating protein subunits called

Answer 14

capsomeres

Question 15

define envelope structure

Answer 15

virus- modified cellular membranes acquired upon exit from host

Question 16

Exposure to ___ solvents in the laboratory renders enveloped viruses ____

Answer 16

lipid

noninfectious

Question 17

Enveloped viruses may have ____ with different structures

Answer 17

nucleocapsids

Question 18

What is the smallest size of virus particle

Answer 18

18 nm

Question 19

What is the largest size of virus particle

Answer 19

300 nm

Question 20

What are the advantages of a large size particle?

Answer 20

Carry a lot of stuff (DNA, etc) EX: herpes

Question 21

What are the disadvantages of large particle?

Answer 21

turnover time isn’t quick (takes a long time to replicate)

Question 22

What 2 types of DNA are in the genome?

Answer 22

single and double stranded

Question 23

What are the 2 types of RNA

Answer 23

double strandard and single stranded

Question 24

What are the 3 types of single stranded RNA?

Answer 24

plus sense
minus sense
ambisense

Question 25

Define plus sense RNA

Answer 25

ready for translation

Question 26

Define minus sense RNA

Answer 26

not ready for translation

Question 27

Define ambisense RNA

Answer 27

a part is ready for translation but another part isn't

Question 28

What are the 4 different types of structure for virus gemone

Answer 28

Linear circular segmented diploid

Question 29

What are the advantages of a large genome?

Answer 29

Make more proteins

Question 30

What are the disadvantages of a large genome?

Answer 30

More things can go wrong More time for the host to attack Harder to replicate

Question 31

What do RNA viruses need that DNA virus do not?

Answer 31

RNA dependent RNA polymerase

Question 32

Virus replication process

Answer 32

``` Attachment ENtry Transcription Translation Replication Assembly Release ```

Question 33

Define attachment

Answer 33

binding of a virus receptor to a cellular receptor

Question 34

What can change the cellular reception?

Answer 34

Genetic engineering

Question 35

What are the 3 cellular receptors?

Answer 35

signaling molecules cell adhesion transport

Question 36

how does a virus usually get into the cell?

Answer 36

cell mediated endocytosis

Question 37

do viral receptors sometimes need co-receptors?

Answer 37

Yes

Question 38

Viral receptors mimic cell receptor's normal ligands T/F

Answer 38

FALSE

Question 39

What do the viral receptors look like on the particle surface?

Answer 39

spike like projections

Question 40

Envelope viruses like to go into the cell by what?

Answer 40

receptor penetration of plasma membrane | influenza, poliovirus, adenovirus

Question 41

What is the other pathway a virus can go into the cell by?

Answer 41

Direct penetration of plasma membrane | HIV, herpes virus, newcastle disease virus

Question 42

How is a virus different from a bacterium?

Answer 42

size

Question 43

How is a virus different from a toxin?

Answer 43

toxin doesn't replicate

Question 44

whats serology?

Answer 44

antibody recognition

Question 45

what is required for replication features?

Answer 45

requires access to cell nucleus

Question 46

what are 2 viruses that are envelopes?

Answer 46

ebola virus and influenza

Question 47

what replication example is dsDNA rolling circle?

Answer 47

herpes virus

Question 48

what are the 2 types of DNA replication?

Answer 48

dsDNA | ssDNA

Question 49

what are the types of RNA replication?

Answer 49

(+)ssRNA | (-)ssRNA

Question 50

what do most DNA viruses need that RNA viruses do not?

Answer 50

DNA- usually needs access to nucleus

Question 51

What are some aspects of the attachment process for viruses?

Answer 51

1. Binding of a virus receptor to a cellular receptor 2. Cellular receptors 3. Viral receptors 4. Genetic engineering (can change receptor recognition)

Question 52

What are the 3 aspects of cellular receptors

Answer 52

signaling molecules cell adhesion transport

Question 53

what is virus tropism?

Answer 53

host range. how much can it infect

Question 54

attachment is a major determinant of ___ ___

Answer 54

virus tropism

Question 55

host range is a major factor in ____

Answer 55

eradication

Question 56

smallpox virus, what host?

Answer 56

only humans

Question 57

yellow fever, what host?

Answer 57

mosquitoes and humans

Question 58

what are the two mechanisms for non-enveloped virus entry?

Answer 58

pores: picornavirus | membrane disruption: adenovirus & reovirus

Question 59

what pathway does an enveloped virus go through?

Answer 59

membrane fusion CELL MEDIATED ENDOCYTOSIS (placed into an endosome)

Question 60

whats an example of enveloped virus?

Answer 60

influenza

Question 61

What are two aspects of the receptor conformational change for entry?

Answer 61

Low pH | receptor induced