Viruses

Question 1

Viruses

Answer 1

Carry very little of their own supplies. They carry little more than info in the form of nucleic acids.

• The info is largely replicated, packaged & preserved by the host cells
• Can be DNA or RNA, have proteins, sometimes have a lipid bilayer membrane they steal from the host
• Viruses also make use of host enzymes, tRNAs, aa, ATP & other molecules

Question 2

Capsid

Answer 2

The protein shell that encloses the viral genome. They are built from protein subunits called capsomeres.

Question 3

Nucleocapsid

Answer 3

genetic material + surrounding protein coat

Question 4

Reverse Transcriptase

Answer 4

An enzyme that takes an RNA template & uses it to make complementary DNA

Question 5

Serves as mRNA

Answer 5

Positive strand

Question 6

Serves as template for mRNA

Answer 6

Negative strand

Question 7

Serves as template for DNA

Answer 7

Retrovirus

Question 8

Bacteriophage

Answer 8

Virus that infects bacteria. Only contains DNA & protein they inject their genetic material

Question 9

Lytic cycle

Answer 9

A phage replicative cycle that culminates in the death of the host cell. This term refers to the last stage of infection during which the bacterium lyses & releases phages that were produced w/in the cell. Each of these phages can then infect a healthy cell & a successive lytic cycle can destroy an entire bacterial population in just a few hours.

Question 10

Virulent phage

Answer 10

If you have a virus that can only replicate by lytic cycle

Question 11

Lysogenic cycle

Answer 11

Replicates the phage genome without destroying the host. Each progeny carries the viral DNA.

Question 12

Temperate phage

Answer 12

Phages that use both the lytic & lysogenic cycles