Viruses

Question 1

viruses are unable to reproduce without a –

Answer 1

host cell

Question 2

because viruses lack typical cell structures such as organelles they are much – than any prokaryotic or eukaryotic cell

Answer 2

smaller

Question 3

virus need – and a protective protein coat (capsid)

Answer 3

genetic material (RNA or DNA)

Question 4

viruses are able to – in that if a viral genome and capsize proteins are mixed together, viral particles will form

Answer 4

self-assemble

Question 5

T/F: viral genome can consists of only a few genes or can range up to a few hundred genes

Answer 5

true

Question 6

viruses are – to the type of host cell that they can infect

Answer 6

specific

Question 7

in order for a virus to infect a cell, that cell must have a – for the virus

Answer 7

receptor

Question 8

while it seems odd that cells would evolve receptors for viruses, it is usually a case of –

Answer 8

mistaken identity

Question 9

viruses can actually – another substance for which the cell has a legitimate need and thus has a receptor for

Answer 9

mimic

Question 10

after binding to a receptor on the membrane of the host cell, viral genetic material enters the host by either injecting itself across the cell membrane or by being taken in by –

Answer 10

endocytosis

Question 11

– are the primary way to induce variation into the viral pop

Answer 11

mutations

Question 12

animal viruses are usually categorized according to the type of – they possess as well as whether it is single or double stranded

Answer 12

nucleic acid

Question 13

once the DNA or RNA of the animal virus is taken in by the host cell, the virus may immediately become – using the host cell machinery to transcribe and translate the viral genes

Answer 13

active

Question 14

the release of new animal viruses can be via – of the cell membrane which immediately kills the host cell

Answer 14

lysis

Question 15

the release of new animal viruses can be via – where the new viruses are shipped out of the host cell via exocytosis

Answer 15

budding

Question 16

T/F: budding does not immediately kill the host cell but may eventually prove fatal to the host

Answer 16

true

Question 17

viruses may become – integrating itself into the chromosomes of the host cell, where it may stay for varying amounts of time

Answer 17

latent

Question 18

eventually the latent virus will – from the host chromosome and it will become active to produce and release new viruses

Answer 18

excise

Question 19

T/F: some viruses are capable of alternating between active and latent forms multiple times

Answer 19

true

Question 20

infections caused by specific – viruses such as cold sores and genital – are notorious for alternating between active and latent forms

Answer 20

herpes

Question 21

first retrovirus discovered

Answer 21

human immunodeficiency virus (HIV)

Question 22

enter the cell in RNA form that must be converted to DNA form

Answer 22

retroviruses

Question 23

process of converting viral RNA backward into DNA

Answer 23

reverse transcription

Question 24

reverse transcription is achieved by an enzyme called – which is present inside the virus when it enters the host cell

Answer 24

reverse transcriptase

Question 25

reverse transcriptase will produce a DNA copy of the RNA, thereby forming a –

Answer 25

DNA/RNA hybrid

Question 26

the same reverse transcriptase will then convert the DNA/RNA hybrid into – that will be converted into mRNA by the virus by using the host’s polymerase

Answer 26

double-stranded DNA

Question 27

In the case of HIV, the DNA integrates into the chromosomes of a host cell (which is a specific cell type in the immune system) and enters a latent phase that may last more than – years

Answer 27

10

Question 28

When the HIV’s DNA excises from the host chromosome it becomes active and begins producing new viruses. When this happens on a mass scale, the death host cells will signal the beginning of deterioration in the immune system, which causes –

Answer 28

acquired immunodeficiency syndrome (AIDS)