Thursday, 28 April 2011


Yesterday, I gave a tour of the department to a thirteen year old and her mother. When I was thirteen, I wanted to be a costume designer for films (blame Lord of the Rings).

No, the girl wasn’t some kind of prodigy (although she did seem pretty smart). Her mum just emailed the head of the department, saying her daughter was interested in science and the university, and they were going to be in the area, so could they come and have a look? And he passed it on, and I volunteered. I was impressed, to be honest, that the girl had that much of an idea of what she wanted to do and was keen enough to want to find out more, which is why I offered to show her around. That, and it was a good break from revising, and it was a chance to practice talking about science to non-experts.

Thursday, 14 April 2011

Blood groups and bruises

Fig 1: I has a bruise.
I went to give blood last Thursday. Giving blood is something I feel quite strongly about, so I try to go as often as I can. Sadly I hadn't been in about a year - but I persuaded a friend to come and donate, too, so I felt less guilty! Unfortunately this time, for me, it didn't go too smoothly. I didn't actually manage to give blood, because the needle went in wrong. Hence the bruise. So I'm going back in a couple of weeks.

After you first give blood, you are sent a donor card, which tells you your blood type. I'm O+ - this was a bit of a surprise to me, as both my parents are A+! A quick Google cleared up why: the A blood group is inherited dominantly, so it's possible for someone to carry one copy of a gene that produces the A antigen, and one copy that doesn't, and still have the A blood group (they are heterozygous). So, both of my parents must carry an A allele and an O allele. (Blood types have actually been used to clear up paternity disputes, before more detailed genetic information was easily available.)

But what do these A, O (and B) things actually mean?