IB Biology Option F SL

1. Viruses IB Biology

2. True or false?

3. Introduction to viruses Smallest living organisms (20nm-300nm) Obligate parasites Only reproduce in living cells Viruses transferred between cells as inert particles known as virions

5. Different Shapes Helical Polyhedral Enveloped Bacteriophage

6. Functions of capsid and envelope Protecting the nucleic acid from enzymes and chemicals when virus is outside host cell Binding to the surface of the host cell Assisting in penetration of the host cell

7. Methods of entry into host cell Direct translocation across the membrane Fusion of viral and cell membranes Uptake by phagocytosis/endocytosis virus Host cell membrane

8. Retroviruses Have RNA not DNA Use reverse transcriptase to change: single strand RNAdouble strand DNA

10. What is a cDNA library? complimentaryDNA (cDNA) cDNA created from mRNA using reverse transcriptase cDNA library : complete set of all the molecules contained within a cell or organism

12. Gene Therapy and Viruses