1. VIRUSES ARE NOT ALIVE BUT AFFECT LIVING THINGS

2. VIRUSES SHARE SOME CHARACTERISTICS WITH LIVING THINGS VIRUSES MULTIPLY INSIDE LIVING CELLS VIRUSES MAY HARM HOST CELLS

3. VIRUSES VIRUS means poison; much smaller than bacteria, can’t even be “filtered” out of a liquid like bacteria can be. Viruses have genetic material inside of a protective protein coat called a CAPSID. They come in many shapes & sizes, but all have a CAPSID and GENETIC MATERIAL. VIRUSES must use a host cell to reproduce (by making genetic material & capsids). Viruses do not grow & don’t respond to changes in the environment, so they are not living organisms

5. Viruses Multiply inside Living Cells Viruses use HOST CELLS to make copies of themselves. A bacteriophage (means bacteria eater) is used to show the process. ATTACHMENT: virus attaches to cell INJECTION: injects its DNA inside PRODUCTION: uses cell’s machinery to copy the viral DNA and capsids ASSEMBLY: viral DNA forces infected cell to assemble new viruses RELEASE: cell bursts open, releasing 100+ new viruses to infect other cells. Viruses have proteins on surface that look like proteins the host cell normally needs to fool it & “dock” onto sites of cell membrane

7. Viruses May Harm Host Cells Virus uses cell’s material, energy, and processes to reproduce often bursting out & destroying the host cell. (some just hide in cell or just make 1 virus at a time & not be as harmful) About 25 million people died of influenza virus in outbreak after WWI. Plant viruses can stunt growth & kill plants Plant, animals, bacteria & all other living things can be infected by viruses. Scientists can use viruses to insert pieces of genetic material into living cells. (like a marine organisms DNA into other tissue causing it to glow so can study it better)