Pure bacterial colonies

    1. When an agar plate is inoculated, why is the loop sterilized after the initial inoculum is put on? 2. Distinguish between a pure culture and a mixed culture. 3. Define a bacterial colony. List four characteristics by which bacterial colonies may be distinguished. 4. Why should a Petri dish not be left open for any extended period? 5. Why does the streaking method you used to inoculate your plates result in isolated colonies?