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I've never done this event before, is it a particularly hard one?

All events are hard at the higher levels

Anyone else gone to a competition yet? Our invites test had 13 stations. Not too much on diseases... but a thing on the bacterial shapes including all the different ones with flagella Other than that and a few other iffy things (dagnabbit - didn't have enough time to write down what, and now I don't remember - I hope we get our test back!), it was pretty easy, though. Two stations on growth rates and such, but that's not too hard.

ophiophagus wrote:

Witchy wrote: To clarify, eukaryotes are often, but not necessarily multi-cellular. Protozoa for example are single celled eukaryotes.

Question: Are Prokaryotic colonies (such as bacterial colonies) considered multi-cellular? I know that the individual bacteria are not, but if someone asked on a test, "Can prokaryotes be multi-cellular?", what would one say?

Bacterial colonies like Volvox are a popular topic of debate for scientists, as they have properties of uni and multicellular organisms, currently I believe scientist do NOT classify them as multicellular because a single bacteria can split off and live its own life or something like that. For the other question, I think (not sure on this) scientists believe that multi-cellular prokaryotes might exist but haven't been found yet or something.
My question: Does anyone have any tips for identifying microbes and/or what type of microscope was used from pictures?

Volvox is an algae, not a bacteria. It is eukaryotic.

psychodragon_98 wrote:arent the prokaryotes multi-celled organisms like us and eukaryotes are single celled, like bacteria?

No

prokariotic = dna in no specific place, mainly bacteria

euchariotic= nucleus, more complex, includes protists fungi, plants, and humans

Flavorflav wrote: Volvox is an algae, not a bacteria. It is eukaryotic.

Sorry about that, flavorflav is correct. However, the members of Volvox are unicellular and volvox colonies behave somewhat like a multicellular organism.

I realize this event is one where experience is limited, and not that many tests have been taken, but do you think it is possible that we would be given a slide of the disease causing agent and then asked to identify treatment/prevention? With no identification of the specimen?

dvd wrote:I realize this event is one where experience is limited, and not that many tests have been taken, but do you think it is possible that we would be given a slide of the disease causing agent and then asked to identify treatment/prevention? With no identification of the specimen?

I would be very surprised to see such a question. This doesn't mean it couldn't happen, but I wouldn't think it would be a wise use of time to prepare for questions like that. You should be able to identify types of organisms by sight (bacilli, cocci, viruses etc.), and you should know which listed diseases are caused by pathogens are of which type, but I don't think many people would be able to answer a question such as the one you propose. There are a few exception - Streptococcus is pretty distinctive - but even here I doubt anyone would expect you to be able to differentiate S. pneumoniae, which causes bacterial meningitis, from S. pyogenes, which causes strep throat.

yousef213 wrote:

psychodragon_98 wrote:arent the prokaryotes multi-celled organisms like us and eukaryotes are single celled, like bacteria?

No

prokariotic = dna in no specific place, mainly bacteria

euchariotic= nucleus, more complex, includes protists fungi, plants, and humans

Sorry for the double, but this is not quite accurate. Bacteria keep their DNA in chromosomes, as we do - usually one circular chromosome, but they can have up to three and they may be circular or linear, and they may have smaller structures called plasmids as well. What they lack is membrane-bound organelles, so the chromosomes are loose inside the cytoplasm, which I think is what Yousef was trying to say.

just curious, we were given a bacterial cell diagram at an invitational competiton recently, and what I thought were cilia were pili, is there anyway that I should've known otherwise? there were already some motile structures on the diagram (aka flagellum)

earthbot25 wrote:just curious, we were given a bacterial cell diagram at an invitational competiton recently, and what I thought were cilia were pili, is there anyway that I should've known otherwise? there were already some motile structures on the diagram (aka flagellum)

I was once in the EXACT same position as you and I said they were cilia and was incredible angry when I saw that it was wrong! But the fact of the matter is (based on my bio textbook) that most prokaryotes (i would say all but there may be some weird exception) don't have cilia. They have pili/fimbrae which help in the genetic exchange of materials (they help the bacteria with reproduction). So if you see stuff that looks like hair on a prokaryotic cell then it's pili/fimbrae NOT cilia.