BIOLOGY - VIRUS LYTIC CYCLE QUESTIONS WITH COMPLETE SOLUTIONS

STEP 1 CORRECT ANSWER virus attaches to the surface of the bacterial cell with tail fibers STEP 2 CORRECT ANSWER virus injects its genome (RNA or DNA) into the cell and viral enzymes break down the cell's DNA STEP 3 CORRECT ANSWER virus DNA directs cell's machinery to make virus parts (CAPSID - copies of viral DNA) (ACCESSORY STRUCTURE) STEP 4 CORRECT ANSWER tail sheath and tail fibers are made and viruses are assembled to form full virus parts STEP 5 CORRECT ANSWER viral enzymes cause cell wall/membrane to burst, releasing many new viruses that go on to infect other cells The yellow ring inside the bacterial cell represents the bacterial DNA. Why does this structure disappear by step 3 of the lytic cycle? CORRECT ANSWER the viral enzymes destroy the cell's DNA and this results in the cell not being able to carry out its normal functions How does a virus destroy the host cell's DNA? CORRECT ANSWER viral enzymes break down the cell's DNA How are new viruses produced? CORRECT ANSWER viral DNA uses the cell's ribosomes to make viral parts (capsid proteins and accessory structures) and uses the cell's enzymes to make copies of viral DNA Why can't a virus reproduce on its own? CORRECT ANSWER it needs the parts of a living cell to make viral