Chapter 22, Problem 8RQ

Many of the first prokaryotes to be cultured in a scientific lab were human or animal pathogens. Why would these species he more readily cultured than non-pathogenic prokaryotes?

1. Pathogenic prokaryotes are hardier than non-pathogenic prokaryotes
2. Non-pathogenic prokaryotes require more supplements in their growth media
3. Most of the necessary culture conditions could be inferred for pathogenic prokaryotes
4. Pathogenic bacteria can grow as free bacteria, but non-pathogenic bacteria only grow as parts of large colonies.