Viruses

Viruses Use infected cell to produce more viruses Capsid: protein coat surrounding DNA/RNA core bacteriophage – virus that infects bacteria

Viral Infections Lytic Infection after entering the cell, host cell make 1000’s of copies of viruse’s DNA new virus particles are made the infected cell then lyses, or busts 100’s of virus particles are released

Viral Infections Lysogenic Infection Prophage: viral DNA become part of the host’s DNA viral DNA is copies with host’s DNA When the prophage is activated, the cell enters the lytic cycle

Retroviruses RNA In host cell, makes a DNA copy of RNA its DNA is inserted into the host’s DNA AIDS

Are Viruses Alive? Not Alive no response to the environment does not obtain or use energy no growth or development reproduces only with a host cell