Chapter 13 - Viruses, Viroids, Prions

Front 1

Characteristics of Viruses

Back 1

-obligatory intracellular parasites

-contains DNA OR RNA

-no Ribosomes

-no ATP-generated mech

-contain protien coat

-some are enclosed by an envelope

-some contain spikes

-most infect specific types of cells in one host

-no cytoplasm

-not living

Front 2

Viruses can pass through ____.

Back 2

Bacteriological filters

Front 3

Host range

Back 3

The spectrum of host cells a virus can infect

Front 4

Most viruses infect only ____

Back 4

Specific types of cells in one host

Front 5

Bacteriophages

Back 5

Viruses that infect bacteria

Front 6

Bacteriophages ranges

Back 6

20 nm to 1000 nm in length (1 macrometer)

Front 7

Virion

Back 7

Complete, fullty developed viral particle

Front 8

Capsid

Back 8

Protien coat made of capsomeres

Front 9

Capsomeres

Back 9

Subunits

Front 10

Envelope

Back 10

Lipid, protien and carbohydrate coating on some viruses

Front 11

Spikes

Back 11

Projections from outer surface of viruses

Front 12

Helical viruses

Back 12

Hollow, cylindrical capsid

Front 13

Polyhedral viruses

Back 13

Many sided

Front 14

Complex viruses

Back 14

Complicated structures

Front 15

Genus names end with ___

Back 15

-virus

Front 16

Family names end with ___

Back 16

-viridae

Front 17

Order names end in ___

Back 17

-ales

Front 18

Viral species

Back 18

A group of viruses sharing the same genetic information & ecological niche (host)

Front 19

Viruses must be grown in ___

Back 19

Living cells

Front 20

Bacteriophages form ____

Back 20

Plaques

Front 21

Plaques

Back 21

Which are clearings on a lawn of bacteria on the surface of agar

Front 22

Each plaque corresponds to a single virus h is is expressed as ____

Back 22

Plaque-forming units (PFU)

Front 23

Growing animal viruses in the lab in what two ways?

Back 23

1. Embryonated eggs

2. In cell cultures

Front 24

Virus growth in embryonated eggs

Back 24

-virus is injected in the eggs

-virus growth is signaled by changes / death of the embryo

Front 25

Virus growth in cell cultures

Back 25

-Tissues are treated w/ enzymes to separate cells

-viral infected cells detected via their deterioration known as CPE (cytopathic effect)

-cont. Cell lines are used

Front 26

Cytopathic effect (CPE)

Back 26

Deterioration from virally infected cells detection

Front 27

Viral Identification (3)

Back 27

1. Cytopathic effects

2. Serological tests

3. Nucleic acids

Front 28

Serological tests

Back 28

-Detect antibodies against viruses in a pt

-western blotting-reaction of a virus w/ antibodies

Front 29

Western blotting?

Back 29

reaction of a virus w/ antibodies

Front 30

Viral multiplication

Back 30

-growth curve

-requires the virus to invade host & take over host's metabolic machinery

Front 31

What does this picture display?

Back 31

One step growth curve

Front 32

Multiplication of Bacteriophages

Back 32

1. Lytic cycle

2. Lyslgenic Cycle

Front 33

Lytic Cycle is defined as ___

Back 33

Phage causes lysis / death of the host cell

Front 34

Lysogenic cycle

Back 34

1. Phage DNA is incorporated in the host DNA

2. Phage conversion

3. Specialized transduction

Front 35

Lytic cycle of T-even Bacteriophages

Back 35

-Attachement

-Penetration

-biosynthesis

-maturation

-release

Front 36

Attachment

Back 36

Phage attaches by tail fibers to host cell

Front 37

Penetration

Back 37

Phage lysozyme opens cell wall; tail sheath contracts to force tail to force tail core h DNA into cell

Front 38

Biosynthesis

Back 38

Production of phage DNA h protiens

Front 39

Maturation

Back 39

Assembly of phage particles

Front 40

Release

Back 40

Phage lysozyme breaks cell wall

Front 41

Lysogency

Back 41

Phage remains latent, dormant

Front 42

Prophage

Back 42

DNA dormant in gene

Front 43

Results in phage comversion

Back 43

The host cell exhibits new properties

Front 44

Specialized bacterial genes

Back 44

Transferred to another bacterium via a phage

Front 45

Animal viruses multiplication steps

Back 45

-Attachment

-entry

-uncoating

-maturation

-release

Front 46

Entry

Back 46

By a receptor-mediated endocytosis / fusion

Front 47

Uncoating

Back 47

Removing of capsole by viral / host enzymes

Front 48

DNA viruses replicate their DNA in ______

Back 48

The nucleus of the host using viral enzymes

Front 49

Synthesize capsid in the ____

Back 49

Cytoplasm using host cell enzymes

Front 50

Virus multiplies in the host cell's cytoplasm using _____

Back 50

RNA-dependent RNA Polymerase

Front 51

3 Types of RNA-dependent RNA polymerarase

Back 51

1. ssRNA + (sense) strand

2. ssRNA - (antisense) strand

3. dsRNA double stranded RNA

Front 52

ssRNA (+) (Sense) Strand

Back 52

Viral RNA serves as mRNA for protien synthesis, single stranded RNA, can be read by ribosomes

Front 53

ssRNA (-) (antisense) stand

Back 53

Viral RNA is transcribed to a + strand to serve as mRNA for protien synthesis, double stranded RNA, cannot be read ny ribosomes

Front 54

Single stranded RNA produce ____

Back 54

DNA

Front 55

Reverse transcriptase is used to ___<

Back 55

Produce DNA from the viral genome

Front 56

Retroviridae (2)

Back 56

1. Lentivirus (HIV)

2. Oncoviruses

Front 57

Viruses can cause several types of ____

Back 57

Cancer