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Flashcards in Viruses Deck (55)
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1

The virus genome typically consist of____-_____ bases or base pairs

5000
100,000+

2

Capsomers

protein subunits that make up the capsid and determine the shape of the virus

3

What shapes can viruses be in?

Helical (ex. tobacco mosaic virus)
Polyhedral (ex. adenoviruses)
Combination of the both (ex. bacteriophages or phages)

4

The____consist of a polyhedral head and a helical tail with tail fibers that attach to a host cell.

T4 phage

5

Enveloped Virus

surrounded by an outer envelope of plasma membrane derived from the host cell. ex. HIV

6

Enveloped viruses produce envelope proteins that extend out from the envelope as_____, which interact with the host cell

spikes

7

Viruses can be classified based on what?

host range
size
shape
Presences of an envelope
Method of transmission

8

_______is based on the type of nucleic acid the virus contains, and how mRNA is produced.

Baltimore Classification System

9

Bacteriophages typically consist of what?

long nucleic acid molecule (usually dsDNA) coiled in a polyhedral head, and a tail that functions in penetration of the host

10

List the 2 types of viral reproduction

Lytic
Lysogenic

11

In a lytic cycle the virus______the host cell

lyses (destroys)

12

Viruses that have only a lytic cycle are what?

virulent menaing they cause disease and sometimes death

13

List the 5 steps to the lytic reproduction

Attachment (adsorption)
Penetration
Replication and synthesis
Assembly
Release

14

When a virus penetrates the host it may what?

completely enter or only the nucleic acid may enter

15

Newly synthesized viral components are assembled into new viruses

yep

16

What type of viruses do not always destroy there host?

Temperate viruses

17

What happens in the lysogenic cycle?

the viral genome usually becomes part of the host DNA and is reproduced along with it

18

What is another name for host bacterial DNA?

prophage (provirus)

19

_____genes may be repressed indefinatly or be triggered by external conditions to go into the lytic cycle

Viral

20

Lysogenic conversion

bacterial cells containing certain temperate viruses may exhibit new properties

21

Give an example of lysogenic conversion

The bacterium Corynebacterium diphtheria only causes diptheria if infected by a specific temperate phage whose DNA codes for the diptheria toxin

22

Viral infections do not usually kill plants, but rather___

stunt growth
change leave shape
cause spots and streaks

23

Most plant viruses have______, but not______.

capsids
envelopes

24

The genome of most plant viruses consist of_____

single-stranded RNA

25

What is the carrier of plant viruses?

insects

26

Plant viruses can be genetic

k

27

How does a virus spread through a plant?

plasmodesmata

28

What are some things viruses cause

chickenpox
herpes
mumps
warts

29

How many viruses a year do humans usually get?

2-6

30

Emerging Diseases

appear suddenly and are new to the human pop.