Thread: Agar plates experiment -Help needed in classifying organisms

hey folks, so basically what i'm doing is the old detergent/agar plates experiment. Trying to determ what detergent works better, and create a link between amount of detergent used to the number of colonies per plate. I want to extend this to what detergent is best at stopping what sort of organism..i think thats the right way to put it. Like which one kills yeasts,bacteria and mold etc. best. I'm in grade 11 Biology, this is for the last part of a portfolio of work. All of which I'm doing very well at! ^_^ I just need some assistance on this one.

I'm struggling to find somewhere in which I can find a similar Dichotimous key, or even labled diagrams would be great, as to determining asto wether something is a bacteria,yeast Mold etc. I know this can be done on a visual basis, but seeing I'm in my first year of bio in highschool I thought i'd be better of going to an outside source for a key. As I lack the knowledge to create one myself.

I want this simply so I have a method that I can attach to my report as to how I classed the colonies on the agar plates. Its nwot a huge drama but would make my report better because I would be able to extend my analysis to what sort of detergent is best at controling what.

Bacteria are typically sleek looking on agar, and will be brownish or white, but some can be red, yellow, gold, and on the right agar some can even be metallic green. Yeast typically make moist looking larger colonies that are elevated and usually are white. It is hard to tell them apart from bacteria on agar without looking at them under the microscope. The yeast will be round and much larger than a bacteria. Molds are fungi like yeast, but they form lots of hyphae and spores so they look fuzzy. Mold is easy to tell apart from the other two because of those macroscopic structures.

If you have access to a microscope it would be much easier to tell them apart.

Edit: If you want general differences between yeast and bacteria try looking up the differences between Prokaryotes and Eukaryotes, that will tell you most of the major physiological differences.

When I completed a similar experiment my cells on the agar were green, blue and purple.