Virus Lecture 17 Flashcards Preview

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Flashcards in Virus Lecture 17 Deck (36):
1

What was the phrase used to describe the first virus in regards to its ability to move through a mesh filter?

Contageum vivum fluidum

2

The first virus found?

Tobacco mosaic virus

3

What was the first animal virus filtered?

Foot and mouth disease

4

T:F Viruses are the most abundant type of biological entity.

True
They are found in almost every ecosystem on earth

5

What is a viruses size?

10^-7 m to 10^-8 m and need an electron microscope to see them.

6

Are viruses intracellular parasites?

Yes. They are obligate intracellular parasites.

7

T:F Viruses are sensitive to bacteria.

False
They are NOT sensitive to antibiotics

8

Are viruses are sensitive to interferon?

Yes

9

How do viruses gain energy?

They take over the host cellular metabolism.

10

T:F Viruses do not have specific hosts?

False
Most viruses are host specific

11

Virion

A complete virus particle that consists of an RNA or DNA core with a protein coat sometimes with external envelopes and that is the extracellular infective form of a virus.

12

Any aspect of the infectious agent and includes: the infectious (Virion) or inactivated virus particle

Virus

13

Why is the study of virology important?

Viruses cause high mortality and morbidity rates and some are zoonotic

14

What is a capsid?

The protein shell of a virus. It usually is symmetrical and used in identification

15

The basic subunit protein in the capsid of a virus is called?

Capsomer

16

Nucleocapsid is?

Capsid + Virus Nucleic Acid (DNA or RNA)/Genome

17

The lipid bilayer with embedded proteins that some viruses have is called?

Envelope

18

What does the envelope do?

Facilitates entry into host and may help with immune system evasion.

19

Virus Genome is either?

RNA or DNA

20

Nucleic acid is either?

RNA
DNA
Both, but at different life stages

21

Shape of nucleic acid

Linear
Circular
Segmented

22

Strandedness

Single
Double
Double with regions of single

23

Sense

Positive
Negative
Ambisense (+/-)

24

Positive sense viral RNA is similar to?

mRNA and can be immediately translated by the host cell

25

What sense viral RNA needs to be converted before translation?

Negative sense, it is complementary to mRNA

26

What are the DNA Viruses

Circovirus
Parvovirus
Hepadnavirus
Papovavirus
Adenovirus
Herpesvirus
Poxvirus
(I need one of Nic's inappropriate acronyms here)

27

What steps must a virus go through to be successful?

Escape from the host or reservoir of infection
Transport to the new host
Entry to the new host
Escape from the new host

28

Vertical transmission

From mother to fetus or newborn at childbirth

29

Transmission between members of the same species?

Horizontal transmission

30

Cross species transmission

Transmission between species

31

Transmission between humans to animals or vice versa?

Zoonosis (anthropozoonosis)

32

Transmission of viral disease?

Person to person
Food and water (fecal-oral)
Insect vectors
Fomites (nonliving objects)

33

Steps virus replication

Attachment
Penetration
Uncoating
Synthesis of viral nucleic acid and protein
Assembly and maturation
Release in large numbers

34

What are the four outcomes for a cell after viral infection?

Cell Death- Lysis, Alteration Cell Membrane, Apoptosis (cell suicide)
No apparent change to infected cell (Latent, Persistent or chronic infection)
Fusion of cells- multinucleated (viral syncytium)
Malignant Transformation (tumor)

35

Characteristics of nercrosis

Chromatin clumping
Swollen organelles
Flocculent mitochondria
Disintegration
Release of intracellular contents
Inflammation

36

Characteristics of apoptosis

Mild convolution
Chromatin compaction and segregation
Condensation of cytoplasm
Nuclear fragmentation
Blebbing
Apoptotic bodies
Phagocytosis