Intro Virology

Question 1

How many nm does virus range

Answer 1

20-300nm

Question 2

What two things does a virus contain and sometimes a third?

Answer 2

nucleic acid
protein sheath
lipid envelope

Question 3

role of protein sheath

Answer 3

carry around nucleic acids

Question 4

how virus reproduce

Answer 4

obligate intracellular parasites

Question 5

location of capsid

Answer 5

outer protein sheath

Question 6

roleof capsid

Answer 6

predominant structure

Question 7

three main capsid “shapes”

Answer 7

icosahedral (roughly spherical)
helical (cylindrical)
complex (combo of the upper two)

Question 8

composition of capsid

Answer 8

collection of individual subunits

Question 9

Icosahedral viruses are composed of repeating subunits called _____, which are composed of ___ individual protein structures, each called a _____.

Answer 9

capsomeres, 5-6, protomer

Question 10

when a lipid membrane from the host is pinched off

Answer 10

enveloped

Question 11

when a virus is considered naked,

Answer 11

only a capsid is surrounding the genetic material

Question 12

places the envelope can come from

Answer 12

plasma membrane, nuclear membrane and cytoplasmic membranes

Question 13

structure to help viruses attach to host

Answer 13

glycoproteins ‘spikes or envelops proteins’

Question 14

layer between proteins and capsid

Answer 14

tegument or matrix protein

Question 15

role of tegument

Answer 15

attach envelope to capsid and delivering viral genetic material/replication enzymes into cells

Question 16

Types of viruses

Answer 16

DNA, ssDNA, dsDNA

RNA, ssRNA, dsRNA, ssRNA(-), ssRNA (+)

Question 17

Sense refers to

Answer 17

reading (translation) direction of genetic material

Question 18

Positive sense

Answer 18

directly translated into viral proteins (5’ to 3’), pracitcally mRNA

Question 19

Negative-sense

Answer 19

complementary strand needed

Question 20

glycoproteins can be on

Answer 20

capsid or envelope

Question 21

a virus can use a _____ to enter a cell

Answer 21

co-receptor

Question 22

name of period when virus injects genetic material

Answer 22

eclipse phase

Question 23

antibodies work only before

Answer 23

eclipse phase

Question 24

two ways enveloped viruses enter

Answer 24

direct fusion

viropexis

Question 25

viropexis

Answer 25

essentially receptor mediated endocytosis

Question 26

envelope fuses with the endosomal vesicle not the plasma directly

Answer 26

viropexis

Question 27

what causes vesicles to open

Answer 27

low pH

Question 28

enters through viropexis but disrupt the endosomal vesicle

Answer 28

naked capsids

Question 29

series of viral genomes

Answer 29

concatemer

Question 30

if replication is done in the cytoplasm, virus must bring its own

Answer 30

enzymes

Question 31

protiens in different batches, expressing their genome in phases, each induced by the proceeding protein products

Answer 31

complex expression

Question 32

name of phase where it remains dormant in its circular configuration within nucleus

Answer 32

latent phase

Question 33

name of phase when replicating

Answer 33

lytic phase

Question 34

RNA (+) reproduce in the

Answer 34

cytoplasm

Question 35

RNA (-) needs to

Answer 35

bring own polymerase, works either in cytoplasm or nucleus

Question 36

Retroviruses can

Answer 36

form DNA from RNA

Question 37

Encapsidation

Answer 37

step wise/regulated assembly of genetic material and capsid protein

Question 38

Ex of bugs that use direct fusion

Answer 38

HIV-1, herpesvirus, paramyxovirues

Question 39

Ex of bugs that use viropexis

Answer 39

influenza, rubella, rabies