1. Viruses Living or Not???

2. Viruses Contain protein and nucleic acids. Do not eat, breathe or perform other biological functions. Can not live on its own, it can reproduce inside living organism that serves as its host.

3. Viruses Host: organism that supports parasite. Viruses instruct host’s cell to produce viruses rather than healthy cells.

4. Classifying viruses Group by disease they cause Life cycle Type of genetic material they contain Basic shape – Crystals: polio virus – Spheres: influenza, HIV – Cylinders: tobacco mosaic virus – Spacecraft: attack bacteria

5. Lytic Cycle Virus finds host cell Enters cells or injects genes into cell Viruses genes take over host cell (virus factory) New viruses break out of host cell to find new host and repeat cycle

6. Lysogenic Cycle Virus enters host No viruses made immediately, but as the host cell divides, copies of the viruses genes passed on to each new cell. Remains inactive until change or stress