Chapter 13

Question 1

Bacteriophage/phage

Answer 1

Virus that infects bacteria

Question 2

Virion

Answer 2

Viral particle,nucleic acid surrounded by protein coat

Question 3

Capsid

Answer 3

Protein coat surrounding nucleic acid of virion

Question 4

Icosahedral

Answer 4

Virus appears round, actual triangular soccer ball

Question 5

Helical

Answer 5

Cylindrival

Question 6

Complex

Answer 6

Intricate structure, phages most common

Question 7

Enteric

Answer 7

Fecal-oral

Question 8

Respiratory

Answer 8

Respiratory or salivary route

Question 9

Zoonotic

Answer 9

Vector ( bugs, mosquitos ) and animal to human direct

Question 10

Sexually transmitted

Answer 10

Sexual contact

Question 11

Lytic/virulent phages

Answer 11

Exit host at end of infection cycle by lysing cell. Forms new virus particles and called productive infections

Question 12

Attachment

Answer 12

Phage attaches to specific receptors on cell wall

Question 13

Genome entry

Answer 13

Tail contracts and phage DNA is injected, phage coat stays outside

Question 14

Synthesis

Answer 14

Phage genome transcribed, phage proteins synthed, phage DNA replicated, virion components made, host DNA degraded

Question 15

Assembly

Answer 15

Phage components assembled into mature virion

Question 16

Release

Answer 16

Bacterial cell lyses, new infectious virions released

Question 17

Burst Size

Answer 17

of phage particles released

Question 18

Lytic Infection

Answer 18

Also called productive infections, release new virion particles during release phase by causing cell to lyse.

Question 19

Lysogenic Infection

Answer 19

Phage incorporates own DNA into host cell genome

Question 20

Temperate Phage

Answer 20

Directs a lytic infection or incorporates own DNA into host cell genome

Question 21

Lysogenic infection

Answer 21

Phage incorporates own DNA into gen ome of host cell

Question 22

Lysogen

Answer 22

Infected cell

Question 23

Prophage

Answer 23

Incorporated Phage dna, can remain indefinitely or be excised by phage encoded enzyme

Question 24

Lysogenic Conversion

Answer 24

Change in phenotype of lysogen as a consequence of specific prophage it carries

Question 25

Filamenrous Phage

Answer 25

Cause productive infections but don't kill host cells. Host cells grow more slowly.

Question 26

Specialized Transduction 1

Answer 26

Temperate Phage injects DNA into bacterial host

Question 27

Specialized Transduction 2

Answer 27

Phage DNA integrates into host cell DNA to become prophage

Question 28

Specialized Transduction 3

Answer 28

Prophage excised from bacterial chromosome and mistake is made, some bacterial DNA is taken and piece of phage DNA left behind

Question 29

Specialized Transduction 4

Answer 29

Replication/assembly produce defective phage particles that carry certain bacterial DNA instead of some phage dna

Question 30

Specialized Transduction 5

Answer 30

DNA of defective phage injected into new host but can't cause productive infection

Question 31

Specialized Transduction 6

Answer 31

Bacterial DNA integrates into host genome via hologous recombination, can now be replicated with host DNA.

Question 32

Restriction modification systems

Answer 32

Protect bacteria from phage infection by quickly degrading incoming foreign dna.

Question 33

Restriction enzymes (many different types)

Answer 33

Recognizes short nucleotide sequences and cuts dna molecule at those specific sequences.

Question 34

Modification enzymes (many types)

Answer 34

Protects host cell DNA from action if restriction enzymes by adding methyl groups to nucleobases recognized by restriction enzymes, making unrecognizable

Question 35

Plaque assays

Answer 35

Used to quantitate phage particles in samples

Question 36

Plaques

Answer 36

Circular zones of clearing

Question 37

Reverse transcriptase

Answer 37

Synthesizes dna from rna template

Question 38

Apoptosis

Answer 38

Programmed cell death

Question 39

Acute infections

Answer 39

Sudden onset symptoms, short duration

Question 40

Persistent infections

Answer 40

Can continue for years, up to life of host, with or w/o symptoms

Question 41

Chronic infections

Answer 41

Continuous production of low levels of viral particles

Question 42

Provirus

Answer 42

virus genome that is integrated into the DNA of a host cell

Question 43

Cytopat ic effect

Answer 43

Distinct morphological alterations in infected cells

Question 44

Inclusion body

Answer 44

Site of viral replication

Question 45

Viroid

Answer 45

Single stranded rna molecule that varies in size and forms a closed ring, so far only infect plants

Question 46

Prions

Answer 46

All protein, accumulate in neural tissue, essentially misfolded proteins. Infectious and non infectious.