25. What are signs of viral growth in embryos? What type of cultures are prepared by placing freshly isolated animal tissue in a growth medium?

25. What are signs of viral growth in embryos?

What type of cultures are prepared by placing freshly isolated animal tissue in a growth medium?

27. What are the primary purposes for cultivating viruses?

28. Do most viral infections result in death?

a.    What are some examples of lethal viruses?

b.    What are some examples of non-lethal viruses?