Science Crime Busters B

[EpicFailure]

What are the ways of identifying hair and fibers if microscopes aren't provided?

[prelude to death]

I guess you could use your hand lens/magnifying glass thingy that you are alowed to bring, according to the rules manual. That would give you a general sense at what kind of hair or fiber it is. Otherwise, maybe the supervisor has burn results or something that you can use to ID the hair/fiber.

[EpicFailure]

At our regionals, we had to identify fibers by look. Also, how deep do we have to know about DNA chromatograms and soil for state?

[prelude to death]

For State, we didn't have anything about soil or spatters... at all. There weren't any plastics for us either. However, we got pictures of blood and stuff and had to match up which suspect's blood was at the crime scene. Also, we had to know how PCR or something like that (can't really remember that well) was used in matching DNA or whatever and what it was. (Sadly, we left it blank because we ran out of time and were rushing to clean up and scatter out the door.)

[northernjacana]

Wait, were you in SoCal? I was in that and we didn't get any bloodstains (that I knew about). We did get large pictures of microscopic hairs and were asked to identify whether they were dog, cat, or human.

[Efficiency]

What are the ways of identifying hair and fibers if microscopes aren't provided?
At our regionals, we had to identify fibers by look. Also, how deep do we have to know about DNA chromatograms and soil for state?

Hmm...
To differentiate between an animal fiber, synthetic fiber, or a vegetable fiber, I used the burn test.
..Animal fiber should burn like hair does -- it should smother..and maybe smell bad.
..Synthetic fiber should shrivel and ignite near the fire.
..I believe, although I'm not completely sure, that Vegetable fibers should have an irregular burn rate and do none of the above. I think.

Also, make sure that the fiber that you test does not touch the flame.

I don't know how to differentiate between cat, dog, and human hair any other way without the microscope.

At my regionals, we weren't allowed to use the burn test to identify the fibers. I ended up panicking and guessing on most of that part >.<
At states they let us use the burn test and also provided the microscopes, which made everything a lot easier and go much quicker.

On both our regionals and state test, both blood spatters and DNA chromatograms didn't appear on the test. So I don't know what you actually really need to know, but from what I heard from other people is that you just need to be able to match up the DNA chromatograms to each other. (Look at the patterns and match the given chromatogram to each of the suspects chromatograms) I don't actually know, but from what I heard it should be pretty easy.

For soil, I'm not sure, because that didn't show up on my test either, but I think it's just the basics, like, matching color, particle, etc. with the crime scene soil and like the soil on the suspects shoes.

Again, haha, this is only what I heard from other people, so I don't really know.

[prelude to death]

Wait, were you in SoCal? I was in that and we didn't get any bloodstains (that I knew about). We did get large pictures of microscopic hairs and were asked to identify whether they were dog, cat, or human.

Yeah... I said that we didn't get any bloodstains, which was sort of weird. Anyways, I didn't exactly know about the large pictures of microscopic hairs, though, since I was testing other things during the time when my partner was investigating the hairs. The fingerprints seemed pretty easy too. They asked us the three basic types of fingerprints (if I'm not mistaken) but my partner and I included more detail than that. In addition, I don't think there were any fibers at SoCal State, but that might just be because I don't remember, since hairs and fibers is my partner's forte. Mixtures and other unknown seemed to be normal. Also, the conclusion was in essay format instead of short answer, which I had during OC Regionals.

[northernjacana]

Oh. I meant that we didn't get any pictures of blood either. We had to identify nine different types of fingerprints. Also, the chromatography was in powders that one presumably had to mix with water and then put it on the paper strip... though my partner was unfamiliar with that, we managed to get 2nd place. I think the essay saved us though (even if I wrote it).

[Sloane57]

Oh. I meant that we didn't get any pictures of blood either. We had to identify nine different types of fingerprints. Also, the chromatography was in powders that one presumably had to mix with water and then put it on the paper strip... though my partner was unfamiliar with that, we managed to get 2nd place. I think the essay saved us though (even if I wrote it).

What do you mean by "nine different types of fingerprints"?

[northernjacana]

Arch, tented arch, radial/ulnar loop, whorl, central pocket loop, double loop, accidental. If you count the central pocket whorl, then that makes nine types of fingerprints. Now that I think about it, we had to identify the eight types of fingerprints (without the central pocket whorl). Nevermind then.