Gen Bio 2 Classification/ Virology

Taxonomy

Science of naming & classifying organisms. Binomial Nomenclature

Phylogeny

Evolutionary History of a species or group of Related species. An evolutionary Hypothesis.

Species is basic level of classification

Domain to species

Monophyletic

Common Ancestor with all its descendants.

Paraphyletic

Common ancestor with some descendants.

Polyphyletic

Missing the Common Ancestor

Obligate intercellular Parassite

Needs to bind to a host cell in order to replicate

Capsid

Protein coat that surrounds the phage

Capsomeres

DNA/ RNA.What the capsid is made out of

Host

Species that is infected when virus attaches

SEQ: General Viral Reproduction Cycle

1.) Virus binds to host Cell

2.) Genome enters Cell

3.) Host Copies Viral genome & produces proteins

4.) New virus Assembles (Assembly)

5.) Virus is Released

The Cycle is applied to all viruses

2 Types of Phage Viruses

Virulent Phage & Temperate Phage

Virulent Phage

Kills the host cell at the end of the cycle. Only applies to lytic cycle

Temperate Phage

Can either use the lytic or lysogenic cycle

Temperate virus hiding using lysogenic may activate. Then it will shut the lytic cycle

2 Reproduction Cycles

Lytic & Lysogenic

Lytic

Kills the host cell at the end of the cycle

Lysogenic

DNA hides in host for many cycles as Prophage. No assembly or release of the virus in the lysogenic cycle

Lytic Cycle

1.) Attachment to Host Cell

2.) Genome enters host cell and host cell DNA degrades

3.) Host Cell produce viral protein and replicates Viral DNA

4.) Assembly of New Virus

5.) Virus is released and cell Lyses

Lysogenic definition and what phage is available

Host survives, Viral DNA hidden inside. Only available in Temperate phage

Lysogenic Cycle

1.) Phage attaches to host cell

2.) Genome enters the cell

3.)Viral DNA is incorporated as Prophage. Produces multiple copies.

How lysogenic cycle makes new phage?

Environment changes in the cell trigger the switch to lytic. So viral DNA can get released to make new phages.