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? 28.

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?

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?