Viruses
Biology: IB Diploma Higher Level, topic 2.9.1
Viruses
Viruses are tiny, non-living (do not have cells) particles that can reproduce rapidly within the body.
Invasion
- To survive and replicate, they invade host cells (animals or plant cells).
Replication
- The virus particle inserts its own DNA into the host cell’s DNA, which is then copied and used to make more viruses.
Invaded cells burst
- Once the new virus particles have been synthesised (made), they cause the cell to burst.
- This releases the new viruses to invade more cells.
Illness
- This cell damage makes us feel ill.
Test yourself on Viruses
How do viruses reproduce? How does this make us feel ill?
Which of the following statements are true of viruses?
Viral Reproduction