SXR103 - Day 3

Another day, another lab but this time we don't start til 9.

So after a quick breakfast in Bramber House it's off to an actual lab for a day of biology.

We all wandered into a rather warm biology lab, find a microscope to perch behind and don our OU lab coats (mine is actually a bit baggy). I had the good fortune to pick a place next to a large fan which made the room seem less like an oven.

After a safety brief we got started by making some qualitative observations wheat plants, aged 3, 7 and 14 days old, some of which have been irradiated with gamma radiation. It has to be said that the irradiated samples do look a little worse for wear although there is some growth visible.




Can you guess which one was nuked??

Next we get a demonstration on preparing a sample of leaf from the 14 day control wheat from our activity tutor (Janet). The catch is that we must prepare a sample that is only one layer of cells thick!!! This consists of gently scraping along the leaf with a razor blade until all the green colour has gone. It's as tricky as it sounds, and my first attempt ended in shreds. Fortunately my 2nd turned out OK so I placed the sample carefully on a slide and stuck it under the microscope.

The next 5 minutes were spent playing "locate the sample in the eyepieces" as we all tried to get the sample in view and in focus, which turned out to be difficult but strangely rewarding when we could see the plant cells we had produced. We then had a go at staining the sample with toluidine blue, which as the name suggests will stain the sample (and anything else it comes into contact with) blue. So we got to don some rather fetching purple gloves and a pair of safety specs just in case, while we drip a bit of stain onto the slide. The next bit was probably the best demonstration of capillary action I have ever seen as we used a tissue to draw the stain from one side of the slide to the other, pure magic!!! The more successful of us get to try with an irradiated wheat sample, with mixed results due to the size of the leaf present.

Then it's time for a quick tea break before we start some proper investigative science. Measuring 2 different types of cells in the coleoptile of both the control and gamma irradiated wheat samples. We were trying to discover why the irradiated samples are much smaller than the control. A bit of statistical analysis later and we determined that it's a mixture of less of one cell and shorter lengths in another (I don't want to give the game away for anyone who might be doing this lab later).

Then it's off to lunch, which was not particularly inspiring so I went for the sandwich option, without the sandwich as they had sold out.

Then back to the lab to look if we could see any mitosis going on in either the control or irradiated samples. This involved extracting a tiny bit of leaf right at the base of the plant, dousing it in a red dye (aceto-orecin), warming it over a Bunsen flame (we had a couple of slides shatter as they were heated too quickly) and then beating the sample flat with a small metal rod. I'll admit that I had no idea what I was looking at but Janet kept enthusing that someone had a sample in prophase or metaphase. We would all dutifully wander over to look at the sample in question and make approving noises.

And then it was time to finish. I have to say I enjoyed the day, it was a little fiddly at times but you got to look at samples you prepared and also prove a hypothesis which was like doing real science.

Tea was better than lunch and I had chicken in Polenta followed by lemon drizzle cake (yum).

I had signed up for an 8:15 lecture giving a taster for S205 which I am starting in September. I killed a couple of hours finishing the day's workbook whilst it was fresh in my mind before wandering off for the lecture just before 8.

This was done by James (the guy from last night) and started well with a talk on what to expect in terms of topics and workload. He also mentioned the new SXx288 Practical Science courses, particularly SXC288 which I'm intending to study in February. Then we sat and watched a 30 minute video on liquid crystals which is part of the S205 course. I found the video interesting but couldn't really see the point in screening it for us if we were going to watch it next year, but hey hoo.

Tomorrow is Rocks and Radioactivity, which is again in the lab and should be interesting.