Lecture 5

Question 1

What are some general characteristics of viruses?

Answer 1

Has DNA OR RNA, protein coat, maybe membrane envelope and protein spikes, no ribosomes

Question 2

What are enveloped virions susceptible to?

Answer 2

Acid, alcohol dryness, heat and UV

Question 3

____ is a complete, fully developed viral patricle

Answer 3

Virion

Question 4

A nucleic acid can be ____ or _____

Answer 4

DNA or RNA

Question 5

A capsid is _____

Answer 5

a protein code made of capsomeres (subunits)

Question 6

What is the enveloped coating on virus made of?

Answer 6

Lipid, proteins and carbohydrates

Question 7

____ are projections from the outer surface

Answer 7

spikes

Question 8

What are some virus morphologies?

Answer 8

Enveloped, polyhedral, helical and complex viruses

Question 9

What are some things that can be done for viral identification?

Answer 9

Cytopathic effects, serological effects and western blotting

Question 10

What are bacteriophages?

Answer 10

Viruses that infect bacteria

Question 11

____ is the spectrum of host cells a virus can infect

Answer 11

Host range

Question 12

What are oncogenic viruses?

Answer 12

Viruses that have become integrated into the host cell’s DNA and induce tumors

Question 13

What are some viral families?

Answer 13

Adenoviridae
Poxiviridae
Papovaviridae
Papillomaviridae
Herpesviridae
Hepadnaviridae
Retroviridae

Question 14

Viruses must be grown in ____ and bacteria are grown in _____-

Answer 14

Living cells
bacteria

Question 15

What must happen for a bacteria to multiply?

Answer 15

It must invade a host cell
It must comandeer the host’s metabolic machinery

Question 16

What are the steps of the bacteriophage lytic cycle?

Answer 16

Attachment, penetration, biosynthesis, maturation and release

Question 17

What happens in attachment?

Answer 17

Phage attaches by the tail fibers to the host cell

Question 18

In ________, the phage lysozyme opens the cell wall; tail sheath contracts to force the tail core and the DNA into the cell wall

Answer 18

penetration

Question 19

What happens in biosynthesis?

Answer 19

Production of phage DNA and proteins

Question 20

____ is the assembly of phage particles

Answer 20

Maturation

Question 21

What happens in release?

Answer 21

Phage lysozyme breaks the cell wall

Question 22

What is generalized transduction?

Answer 22

When any bacterial genes are transferred

Question 23

What is specialized transduction?

Answer 23

When specific bacterial genes are transferred

Question 24

What is lysogenic conversion also called?

Answer 24

Phage conversion

Question 25

Where can animal viruses be grown?

Answer 25

In living animals, embyonated eggs and cell cultures

Question 26

What makes more mistakes and what tolerates these mistakes?

Answer 26

Viral polymerases makes more mistakes; non cellular genomes tolerate more mistakes

Question 27

For viral taxonomy, what do the order, family and genus names end with?

Answer 27

Order: -ales Family: -viridae Genus: -virus

Question 28

Family, genome and method of transmission for HEV

Answer 28

Family - hepeviridae Genome - ssRNA (+) Transmission - fecal-oral, parental

Question 29

What diseaeses do influenza viruses A and B cause?

Answer 29

Seasonal epidemics

Question 30

What diseaeses do influenza viruses C cause?

Answer 30

Mild ilnesses

Question 31

What diseaeses do influenza viruses D cause?

Answer 31

Diseases affecting cattle

Question 32

What are prions ans examples of diseases that they cause?

Answer 32

Prions are proteinaceous infectious patricles, some examples of diseases are Mad cow disaese, fatal familial insomnia, spongiform encephalopathy

Question 33

Features of viroids

Answer 33

RNA, no protein coat, only infects plants, replicates in nucleus or chloroplast

Question 34

________ are eukaryotic organisms that are not animal, fungus or plants and are usually unicellular

Answer 34

Protists

Question 35

Animal-like protists are ____, plant-like protists are ____ fungus-like protists are ________

Answer 35

Motile heterotrophs Photosynthetic autotrophs Spore-forming heterotrophs

Question 36

What are some modes of reproduction in protists?

Answer 36

Binary and multiple fission Plasmotomy Budding Syngamy Conjugation