As you may have noticed, during the spring I have studied some biology. Five high school courses worth, to be exact. I just finished with the last one a couple of days ago.
Anyway, a lot of it left me with some questions. Mostly about biotechnology, or stuff somehow related to it, because it was the topic I covered last, so it's the one I remember the questions that came to mind. Also, a lot of the questions I got earlier I asked about from a friend or dad, and got an answer already. He would probably know the answers to these ones, too.
*When you get a transplant, you start taking medicine to suppress your immune system, so that it doesn't attack the new organ. But isn't it dangerous? Autoimmune diseases that naturally suppress the immune system are bad, so why is suppressing your immune system on purpose not bad?
*On the same note, do people actually die of AIDS? Meaning do people die of AIDS as such or a cold that they have no way to stop because AIDS has wiped out their immune system? The same way I suppose people don't die of being old, they die because of a simple infection because they're too old to fight it any more. I suppose. Is it possible to die of just being old? And (jumping back to the original question) if people die of colds, then is the cause of death AIDS or a cold?
*Is it possible to have unidentical conjoined twins? What is now known of how conjoined twins form, it's either that the embryo starts to separate, but doesn't part all the way, or that it separates into two that then partly fuse back together. Apparently it is not known, which. Anyway, there are chimeras (that I know you know about), that are people or any other organisms, that have two separate sets of DNA in their cells (not in the same ones), because they were once twins that then fused into one when they were still only lumps of cells. Ok, so if conjoined twins are formed by twins partially fusing together, and it is possible for unidentical twins to fuse completely together, then can there be unidentical conjoined twins?
I actually called dad and asked about this, and he said technically probably yes, but he'd never heard of any. Also, Wikipedia defines conjoined twins as "identical twins joined in the utero". So in the end, I'm left not knowing if it is possible.
*Why does kids' sweat not smell? Ok, sweat as such doesn't actually smell like anything, it's the bacteria feeding on the sweat on the skin that smell bad. And people generally start smelling bad at puberty, so that then you have to start showering more than once a week and using deodorant and all kinds of stuff to stop that smelling. So why don't kids smell? They're lacking the bacteria? If yes, then why, and if not, then what? Or is there another reason than sweat to why kids don't smell the same way as adults? Like hormones and pheromones?
That's the biggest questions from the last few days. My own guess for the answers are: not too bad - no - no, though I really want to know why - there is something particular in sweat that the bacteria eat, and it's secretion only starts at puberty. But I don't actually know. That's why I'm asking. So if you're running low on stuff to write about, you could dig out the correct answers for me.
The problem with me is that I want to know a lot of stuff, but I'm really lazy to start digging up information about the stuff I want to know, which is stupid, since in today's world finding information about anything is ridiculously easy.
Also, after studying all of Finnish high school biology in a couple of months, I am once again completely stunned by DNA. I mean, the structure of DNA isn't all that complicated, since it can be broken down to just a few simple small molecules, and yet it keeps inside it the instructions for... everything. And most of it doesn't even do anything. The portion that actually codes for proteins is tiny compared to the amount of DNA in every single of our cells, which is about two meters per cell. Yes, we have two meters of DNA in every single of our cells. Thinking how small the diameter of DNA is, that is a lot.
The point is I just want to go outside and stare, because that's how amazing is the fact that a something like DNA an do all that you see outside.
I guess this is what religious people feel like when they think about how a god created everything. Though, honestly, I think a single molecule doing all that is way (WAY) more impressive than if it was an omnipotent being, since one of those could literally do anything, so that kind of takes the whole wonder of all this existing away. But a single molecule... wow. That is amazing.
Anyway...
That's all for today. I'll hear from you on Friday.
~matu
Also, thanks to the birch right outside my window, I've been wondering why antihistamine (it's either that or the allergy itself, and a couple of friends have said it's the medicine) makes people tired.
ReplyDelete~matu
Since some of these questions seem to be right up my lane, I thought I'll post my first-ever comment on your blog :-)
ReplyDeleteSuppressing the immune system: yes, it is dangerous. That's why transplant patients need to be very careful not to get infections, and they also use a lot of antibiotics in the first months after the operation. As to autoimmune diseases, these imply that the immune system is active where it should not be, and attacks the body's own tissues.
Dying of AIDS or old age vs. a cold: I guess this is a question of ultimate vs. proximal causes. The proximal cause of death may be the cold, but the ultimate reason why the cold became lethal was weakening of the body by AIDS/old age.
Non-smelly kids: Humans have two kinds of sweat glands, eccrine glands and apocrine glands. Eccrine glands are all over our body and they cool us down when we get hot. Eccrine sweat consists mainly of water and salt. Apocrine glands are only found in a few places, e.g. in the armpits and around genitalia, and they produce an oily liquid that acts as a pheromone and turns smelly when bacteria get their way. And - bingo - apocrine glands are inactive in children and only start operating at puberty. Interestingly, non-human primates have aprocrine glands all over their bodies as they use the apocrine sweat for cooling, whereas they use eccrine sweat to get a better grip of branches with their hands and feet (and tails, in those species whose tails are prehensile) so eccrine glands are restricted to those parts.
DNA: I agree, it's amazing. And the more you learn about biochemistry, the more amazing it seems that any of it can function at all... By the way, the view that most of our DNA is inactive junk is changing, as more and more things that the non-protein-coding parts actually do are found. For example, they seem to be quite important in regulating the activities of other genes.
Cheers,
Hanna