Review Sheet 5: Viruses

Question 1

3 Characteristics of Virus

Answer 1

1. Acellular
2. DNA or RNA
3. Cannot replicate outside of a host cell

Question 2

Phage

Answer 2

Virus that infects bacteria or archae

Question 3

Virion

Answer 3

An individual virus particle

Question 4

Capsid

Answer 4

Protein coat that surrounds nucleic acid

Question 5

Nucleocapsid

Answer 5

A Nucleic acid surrounded by a protein coat

Question 6

Envelope

Answer 6

Some viruses have it, surrounded by membrane

Question 7

Spike/Peplomar

Answer 7

Viral proteins embedded in envelope. Recognizes cell surface

Question 8

2 Specific spike proteins

Answer 8

Hemaglutanin and Neuraminidase

Question 9

Protomer

Answer 9

Individual Protein coat molecules

Question 10

Receptor protein

Answer 10

Whatever virus binds to during adsorption

Question 11

Viroid

Answer 11

Virus without capsid and only RNA

Question 12

Nucleic Acids in Cells v. Viruses

Answer 12

Viruses have HMC as well as ATGC

Question 13

Segmented/Nonsegmented

Answer 13

More than 1/ 1 nucleic acid molecule

Question 14

of strands

Answer 14

+ (Sense) stranded same as mRNA

- (Anti-sense) opposite

Question 15

4 Capsid Shapes

Answer 15

1. Icosohedral
2. Helical
3. Binal
4. Complex

Question 16

5 Steps in Viral Reproduction

Answer 16

1. Adsorption
2. Entry into Host
3. Synthesis of Phage Components
4. Particle Assembly
5. Virion Release

Question 17

How Enveloped viruses enter host cell

Answer 17

Fusion

Question 18

How non-enveloped viruses enter the host cell

Answer 18

Endocytosis or DNA injection (IE T4)

Question 19

Polyproteins

Answer 19

1 Protein cut into smaller functional pieces

Question 20

Replicative Viral DNA (RF)

Answer 20

Nucleic acid used to make copies. Inside host, not virus.

Question 21

DNA Polymerase

Answer 21

(SS) DNA dependent (DS) DNA polymerase

Question 22

RNA Polymerase

Answer 22

DNA Dependent RNA polymerase

Question 23

Replicase

Answer 23

RNA Dependent RNA Polymerase

Question 24

Reverse Transcriptase

Answer 24

RNA Dependent DNA (SS) Polymerase

Question 25

Retroviruses

Answer 25

Reverse transcriptase, inserts DNA into host DNA

Question 26

How enveloped viruses exit cell

Answer 26

Budding

Question 27

How non enveloped viruses exit cell

Answer 27

Exit by lysing cell

Question 28

Lysogeny

Answer 28

Passive replication of phage

Question 29

Temperate phage

Answer 29

Any virus capable of lysogeny

Question 30

Prophage

Answer 30

Just inserted phage, no proteins

Question 31

Induction

Answer 31

Switching lysogeny —> Lytic

Question 32

Repressor Protein

Answer 32

Keeps phage from being transcribed

Question 33

Cytocidal Infection

Answer 33

Kills cell it infects

Question 34

Acute infection

Answer 34

Short lasting, rapid reproducing (ie cold, flu)

Question 35

Chronic infection

Answer 35

Persists for a long time always active (ie HIV)

Question 36

Latent infection

Answer 36

Persists for a long time
Can be dormant
caused by retrovirus in eukaryotes

Question 37

6 Viruses that cause cancer

Answer 37

1. Epstein-Barr
2. Hepatitis
3. Pipillomavirus
4. Herpesvirus8
5. HTLV1/2
6. Rous Sarcoma

Question 38

Epstein-Barr Virus causes…

Answer 38

Burkitt’s Lymphoma

Question 39

Hepatitus Virus (B/C) causes…

Answer 39

Liver Cancer

Question 40

Papillomavirus causes…

Answer 40

Cervical Cancer

Question 41

Herpesvirus 8 causes…

Answer 41

Kaposi’s sarcoma

Question 42

HTLV 1/2 causes…

Answer 42

Leukemia

Question 43

Rous Sarcoma Virus causes…

Answer 43

Cancer in chickens. 4 genes

Question 44

gag

Answer 44

Encodes a capsid protein

Question 45

pol

Answer 45

Encodes reverse transcripterase

Question 46

pro

Answer 46

encodes envelope protein. Binds host cell

Question 47

SRC

Answer 47

(V src = viral src) Causes cells to become cancerou

Question 48

Plaque

Answer 48

An area cleared of bacteria by virus

Question 49

5 ways to measure amount of virus

Answer 49

1. Counting
2. PFU
3. Hemaglutination Assay
4. LD50 (Lethal Dose)
5. ID50 (Infectious Dose)

Question 50

Virus Classification

Answer 50

1. Type of Nucleic Acid
2. Shape of Capsid/Envelope
3. Type of host
4. Nucleic Acid Sequence