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* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Viruses Is a virus living like a cell? Achoo!! Sneezing is an involuntary action that aids the body by clearing congestion within the nose. But sneezing also spreads viruses. 1. What happens if a virus enters your body? What are some symptoms? 2. What can you do to limit the spread of viruses? What is a Virus? Is it living or nonliving? NON-LIVING Why would we think it’s living? Has DNA Can Reproduce What is a Virus? A strand of DNA surrounded by a protein coat. Virus Multiplication Viruses can make copies of themselves only inside a living host cell. Virus Multiplication Active viruses – make the host cell create new viruses, which kills the host cell. Latent viruses – hide in the host cell without destroying it. Virus hereditary material becomes part of the host cell hereditary material. Latent viruses can become active and then destroy the host cells. I’ll hide out! They’ll never find me! Effects on Organisms Most viruses infect only specific kinds of cells. Viruses are often carried to the host through the air. The virus and host cell must fit together exactly to begin a viral infection. Effects on Organisms Bacteriophages attach to bacteria and inject their hereditary material. Fighting Viruses Vaccines – weakened virus particles that allow the host to fight some diseases. Treating viral diseases Antibiotics are not effective treatments for viral infections. Infected cells sometimes produce interferons which are proteins that can protect noninfected cells. Antiviral drugs often have adverse side effects, limiting their use. Public health measures can prevent or slow disease. Research Gene therapy uses viruses to replace defective cell hereditary material with normal cell hereditary material. Viral Reproduction 1. The virus attaches to a specific host cell. Viral Reproduction 2. The virus’ DNA enters the host cell. Viral Reproduction 3. The DNA of the virus causes the cell to make copies of itself! Viral Reproduction 4. New viruses form inside the host cell. Viral Reproduction 5. New viruses are released as the host cell bursts open and is destroyed.