Viruses

Question 1

Virus

Answer 1

infectious particle of genes packaged in a protein coat

Question 2

Different genome shapes

Answer 2

Double-stranded DNA/ Single-stranded DNA
Double-stranded RNA/ Single-stranded RNA
Single linear/ Single circular / Multiple pieces

Question 3

Capsid

Answer 3

protein shell enclosing the viral genome

Question 4

capsomere

Answer 4

protein subunit of a capsid

Question 5

Rod-shaped

Answer 5

helical virus

Question 6

Polyhedral

Answer 6

icosahedral virus

Question 7

Complex

Answer 7

icosahedral head + helical tail

Question 8

Envelope

Answer 8

membrane derived from host cells that surround many animal viruses

Question 9

An envelope is made of

Answer 9

Phospholipids & membrane proteins from host cells, Glycoproteins and enzymes of viral origin

Question 10

Obligate intracellular parasite

Answer 10

can only replicate inside a host cell

Question 11

Viruses lack enzymes for ____

Answer 11

making macromolecules

Question 12

Host range

Answer 12

limited # of species a virus can infect

Question 13

Host range is controlled by __

Answer 13

Lock & key fit of viral surface proteins and receptors on host cells

Question 14

West Nile Virus

Answer 14

infect mosquitoes, birds, horses, and humans

Question 15

Measles affect

Answer 15

humans

Question 16

Bacteria virus

Answer 16

Phage

Question 17

Lytic cycle

Answer 17

replicative cycle that ends in death of host cell

Question 18

Virulent phage

ex. E.T4 phage

Answer 18

virus that is replicated by a lytic cycle

Question 19

Attachment

Answer 19

T4 phage uses tail fibers to bind specific receptors on outer surface of E.coli cells

Question 20

Entry

Answer 20

T4 phage DNA is injected into cell

• Empty capsid left outside
• Host DNA is hydrolyzed (degraded)

Question 21

Synthesis

Answer 21

viral genome/proteins are produced using host components

Question 22

Assembly

Answer 22

virus genomes packaged into capsids

Question 23

Release

Answer 23

viral enzymes break down cell wall

- cell bursts and 100-200 viral particles pop out

Question 24

Lysogenic cycle

like zombies, which are..unhygenic. they have lice, … lice-unhygienic, lysogenic

Answer 24

replicative cycle that does not destroy the host cell

Question 25

``` Temperate phage (ex. lambda phage) ```

Answer 25

a virus that uses both lytic & lysogenic cycles

Question 26

Prophage | pro, because, they're evil pro-ph-agents

Answer 26

viral DNA integrated into host genome

Question 27

Replication

Answer 27

every time the host divides, the viral DNA is copied to new daughter cells

Question 28

Lytic cycle

Answer 28

can be triggered by environment changes

Question 29

Bacteria defenses

Answer 29

Diversity, Restriction enzymes, CRISPR-cas system, Evolutionary arms race

Question 30

Restriction enzymes

Answer 30

bacteria enzyme that recognizes foreign DNA entering the cell & cuts them up

Question 31

Bacteria DNA is methylated to ____

Answer 31

protect from own restriction enzymes

Question 32

CRISPR-cas system

Answer 32

long-term, targeted defense against a specific virus - piece of DNA from phage is incorporated into CRISPR

Question 33

Cas proteins

Answer 33

nucleases that cut up DNA identified in CRISPR

Question 34

Evolutionary arms race

Answer 34

bacteria evolve to avoid virus infection. Virus evolve to beat bacterial defense.

Question 35

Animal viruses

Answer 35

have envelope derived from host cell

Question 36

Envelope glycoproteins bind to ___

Answer 36

specific receptors on WBC

Question 37

Envelope fuses w/ ___

Answer 37

plasma membrane, releasing capsid into cell

Question 38

Host cell enzymes break down ___

Answer 38

capsid, releasing viral genome

Question 39

Reverse transcriptase enzymes copies ___

Answer 39

viral RNA

Question 40

Gene expression of viral proteins

Answer 40

- Glycoproteins - Capsomeres (subunits needed to make capsid) - Reverse transcriptase

Question 41

Capsids are assembled and ___

Answer 41

glycoproteins transported to membrane

Question 42

Vaccine

Answer 42

harmless derivatives of a pathogen that stimulates the immune system to mount a defense against it

Question 43

Virus

Answer 43

smallpox, polio, measles, rubella, mumps, hepatitis B

Question 44

Viroid

Answer 44

infectious circular RNA molecules, have no capsids

Question 45

Prions

Answer 45

infectious self replicating protein, no DNA/RNA

Question 46

Plasmids

Answer 46

small circular DNA molecules that can be shared between bacteria

Question 47

Transposon

Answer 47

DNA segments that can jump to different parts of the genome