Ms. DNA

I'm just curious, Hades; how are you going to store those chemicals? Do you have a storage cabinet for the acid? If you don't have one, maybe you can order one from a lab supply company.

G

punctuation

Basically, he means onsite.

faked

(I wasn't sure if this topic should go here or in the news forum. Feel free to move it if necessary.) According to a paleontologist from Princeton, the asteriod that fell in the Yucatan and is commonly believed to have killed the dinosaurs may not have been the chief cause of their extinction. Studies of rock formations in the area suggest that the asteriod fell about 300,000 years after the dinosaurs became extinct and that the crater is smaller than originally thought. Microfossils also suggest that the many organisms were already endangered before the asteriod fell, and the asteriod may have been the "final straw." Here's the link to the complete article: http://www.cnn.com/2004/TECH/science/03/02/coolsc.dinosaurs.extinction/index.html

bubbles

I took AP exams in English and chemistry many moons ago; I got 5's on both tests. I earned enough college credits to get sophomore status after one semester, which was helpful for registeration. Unfortunately, I had to take a different intro chemistry course for my major than the one I got credit for, so a few semesters later, the extra credits were taken away. It was still worth taking the tests and getting the credits, though.

What about the role of our own daily habits in promoting good health? Sleep, exercise, and good nutrition (or the lack thereof) all play a role in your general health; are you counting them? Perhaps natural selection would reduce the number of couch potatoes in the general population. And I don't think you can consider all diseases "outside" influences, as many of them have some genetic component.

Statistics.

I should have been clearer about why it's easier to make sperm instead of eggs. Sperm cells do not need as much cytoplasm and associated organelles as eggs do. You can split a precursor cell into four sperm, and they'll all be viable. But an egg needs to retain as much of its cytoplasm and organelles as possible; otherwise, it won't survive. When the precursor of an egg cell goes through meiosis, one daughter cell is almost the same size as the original cell, and the other daughter is very small and consists mostly of genetic material. The small daughter cell is called a polar body; it isn't viable. So if you're making gametes, you can make four sperm from one precursor, but you get only one egg and three polar bodies if you're making eggs. I probably should have said it's more efficient to make sperm, but I was in a hurry to get to lunch. Does that make sense, mooeypoo? And has this answered your question?

I've seen the terms used interchangably, but I've also seen "oocyte" used to refer to an immature egg. The precursor cells that produce eggs and sperm have to divide twice (meiosis), and oocytes are "frozen" between cell divisions. One of them each month in a fertile woman will divide again, and one daughter cell will get most of the cytoplasm and form the mature egg. Here's a link: http://www.medfac.leidenuniv.nl/heelkunde_onderwijs/IMM/imm39.html As to mooeypoo's question, I think sperm only survive a few days; they're being constantly created and reabsorbed. It's easier to make sperm than eggs anyway, since you can create four sperm cells from a single precursor. So it wouldn't make sense to store them the way immature eggs are. But someone else here might know more about sperm than I do.

Eggs develop from oocytes, which are contained in follicles.

I haven't posted my first name yet. It's Sandra.

Population growth isn't uniform all over the world. In developed countries (such as the U.S. and Europe), population growth has slowed. I think it might even be negative in a few countries, such as Japan. Developing countries, on the other hand, still tend to have higher population growth. One factor in population growth is female literacy. The better educated a women is, the fewer children she has. Population programs are encouraging literacy programs in developing countries as a way of slowing population growth. Here are a few links that might be of interest: http://www.census.gov/main/www/popclock.html http://www.populationconnection.org/ http://www.npg.org/ http://www.census.gov/ipc/www/world.html http://www.wri.org/enved/pop-1a.html http://www.wri.org/enved/pop-1h.html

I too would like to know where you found this information, alt_f13. If this is really true, I must be in the other 1.6% of women, then. I'm almost afraid to ask what the majority of men use the Internet for.

I'm not sure if this topic belongs here or in the News Forum, but I'll put it here and let the moderator decide. I read an article in the New York Times that claims the Bush administration routinely distorts scientific facts to further its policies. Here's the link: http://www.nytimes.com/2004/02/19/politics/19RESE.html?th (You may need to register to read the article, but registration is free.)

I Googled "Hawking radiation" and found a couple of sites that might answer the question: http://math.ucr.edu/home/baez/physics/Relativity/BlackHoles/hawking.html http://casa.colorado.edu/~ajsh/hawk.html

Crunchy.

I got sunburned a few years ago when I went to the beach. I only got sunburned on my back, where I couldn't apply sunscreen properly. So sunscreen has to do something to protect the skin. And if your skin turns red, isn't it already damaged?

Yeast can metabolize glucose by either of two pathways, either with or without oxygen. Without oxygen, it can't process glucose as completely, and that's when the yeast produces alcohol. It does make CO2 when it uses oxygen. Here's a link with more information.

Genes may set the potential, but the environment affects gene expression. Twins would share the same prenatal environment (though one could affect the other's environment by taking more of the nutrients). In most instances, they would be reared together as well. With clones, you can raise the clone in a completely different environment. A clone could even be of a different generation than the person s/he was cloned from. So I think a clone would be less like the original person than identical twins are like each other.

The theory Yoshmaista is talking about is one of Zeno's paradoxes. Zeno was a Greek philosopher. You can learn more abut him and this paradox here: http://www-gap.dcs.st-and.ac.uk/~history/Mathematicians/Zeno_of_Elea.html