Apowers1991

I just need to be pointed in the right direction so I can figure these answers out. Thanks in advance for anyone willing to help. 1. Culture media must provide many essential components in the artificial environment of a broth or solid medium. List the minimum items that must be provided for the successful growth of organisms and indicate what their role is for the organisms. 2. In addition to the items listed above, what other considerations must be considered once you have provided the above list and why? 3. Water from the tap is rarely ever used to make medium. Why? 4. How are selective and differential media different. How can the two be combined in a useful way? 5. After the addition of water to the powdered medium it must be sterilized in a timely fashion. Why? 6. What is the major difference between the preparation of a broth medium and one containing agar? 7. What are the major problems encountered when counting bacteria using a diluted sameple on a microscope slide? 8. Why do we use pipets to perform our dilution sequences rather than the inoculating loops? Does it make a difference in using pour tubes for our dilutions rather than dilution blanks? why? As for what I know: 1. I know the items needed to have a successful growth but I'm not sure which ones can be left out. 2. I just don't understand this question. 3. I know that tap water contains contaminates but I thought that mediums had to be sterilized so should tap water matter? 4. I know how they are different but I have no idea about how they can be combined. 5. The powdered medium is agar. I think the answer is because it needs to be sterilized before it turns into a solid. Agar which is very time sensitive. Am I close on this one?? 6. I'm still very new to the microbiology stuff and for some reason I thought all mediums contained agar so I'm not sure about this question. It just confused me. 7. I don't know what kind of problems could arise. 8. The only things I can think of is because dilution is very sensitive to amounts. The inoculating loops don't have a set amount of liquid that can be picked up. I don't know what a dilution blank is. I understand this is not for answers and I want to point out that I am not looking for anyone to do this for me, but I am looking for help. I've tried. I've read and re-read my lab manuals and book but I am still having problems.