2006-12-23 12:38:14 · 4 answers · asked by Alex 2 in Science & Mathematics ➔ Biology
I just found a newly published article I can't understand, http://www.jstage.jst.go.jp/article/jrr/47/SupplementB/B75/_pdf I
2006-12-23 13:04:15 · update #1
It is an extremely interesting article.
How did you come across it?
Sperm cells cannot repair DNA. Not only they lack the other chromosome to "compare", but everything is packed, and the cell load is minimized to what is necessary for the sperm to deliver the DNA (and the centriole) inside the egg.
According to the article it is not the "damaged" sperm that is favoured. They claim that:
The germ cells which produce sperm cells can accumulate mutations. These mutations, although they will be bad for the cells in the body of the offspring, they can sometimes give a selective advantage to germ cells that carry them, over the rest of the germ cells of the father. In such cases, you have more mutated sperm cells being produced (since the cells which produce them have an advantage over the cells that would produce sperm with "normal" DNA).
Here I should point out that the sperm cells are not damaged, but their DNA is. This is important to understand because they will swim equally well as the sperm cells with non damaged DNA; the "messengers" are equally potent but the "message" they are carrying is compromised.
2006-12-23 22:28:55 · answer #1 · answered by bellerophon 6 · 0⤊ 0⤋
The repair mechanism requires a set of homologous choromsomes. So, if the DNA is damaged, the sperm cell is unable to repair because it does not have a corresponding pair.
I do not think that the testes favour any sperm. Be it wrong shape or damaged DNA. It just stores the sperms at the right temperature. However, we would generally want non-damaged sperm cell because of the obvious reasons.
2006-12-23 12:45:20 · answer #2 · answered by PIPI B 4 · 0⤊ 0⤋
Sperm cells can not repair DNA, the testes do not favor damaged sperm. It would select against the damaged ones,
2006-12-23 14:01:14 · answer #3 · answered by science teacher 7 · 0⤊ 0⤋
Yeah.. Fingerprints only come into play after like.. what, the third month with a remainder of two weeks? The baby becomes more and more defined after the first month. Most people get an abortion towards the middle of the second month or within the next two weeks of conception. This is what you fail to realize because you assume that "liberals" wait until the 4th trimester to abort the child.
2016-05-23 02:51:26 · answer #4 · answered by Anonymous · 0⤊ 0⤋