Search found 106 matches

by AstraSequi
Tue Mar 27, 2012 2:30 am
Forum: Evolution
Topic: Theories - Origin of Life
Replies: 563
Views: 1819244

It depends what you mean by "unlikely." While any individual mutation is unlikely, that doesn't mean that it will not happen on a regular basis if you give it enough chances. So the question therefore must be, how many chances does “enough” mean? It depends on exactly how confident you wa...
by AstraSequi
Tue Mar 27, 2012 2:28 am
Forum: Evolution
Topic: Theories - Origin of Life
Replies: 563
Views: 1819244

Again, the possibilities are: - the mutations might be common enough that they happen all the time - the mutations might occur once or twice and then spread through the population by interbreeding - the mutations might have already been present in the ancestral population From my post above, I thin...
by AstraSequi
Tue Mar 27, 2012 2:25 am
Forum: Evolution
Topic: Theories - Origin of Life
Replies: 563
Views: 1819244

There are random mutations that rearrange the DNA of the cell. These mutations are invariably the result of copying errors, breakdown in regulating functions like error correction, and DNA damage from environment like from chemical or UV radiation sources. I agree, although I will point out that no...
by AstraSequi
Tue Mar 27, 2012 2:23 am
Forum: Evolution
Topic: Theories - Origin of Life
Replies: 563
Views: 1819244

Re: Theories - Origin of Life

So can we agree on what each of us means when we use the term mutations. As I have demonstrated there are differing views on what constitutes a mutation. The talkorigins essay by Richard Harter states that :- It is important to realize that mutations do not occur in response to the environment. The...
by AstraSequi
Tue Mar 27, 2012 2:21 am
Forum: Evolution
Topic: Theories - Origin of Life
Replies: 563
Views: 1819244

Re: Theories - Origin of Life

I’ve been thinking about the comments earlier, and I realized while writing it that the discussion has started to get less useful for me as well – not least because of how much time it’s taking (this reply took ~12 hours to make, including all the researching, and it is ~26 pages long in Word). As a...
by AstraSequi
Mon Mar 26, 2012 6:01 am
Forum: Human Biology
Topic: Genetic/Chromosomal testing from autopsy of miscarried baby
Replies: 7
Views: 15717

Don't forget that the "inverted 10" of one person is not necessarily the same as in another person. All it means is that somewhere on chromosome 10, there is a sequence of DNA (long or short) that is in reverse order compared to most people. For example, if one end of the inverted region f...
by AstraSequi
Sat Mar 24, 2012 7:23 am
Forum: Cell Biology
Topic: Help on stem cells
Replies: 1
Views: 2288

I think the main reason is defense against cancer. Every division is a chance for mutations, and If you had the already-existing cells dividing, then they would build up mutations fairly quickly. However, you can instead have a stem cell divide once (producing one daughter cell and one cell which re...
by AstraSequi
Tue Mar 20, 2012 9:16 pm
Forum: Evolution
Topic: Theories - Origin of Life
Replies: 563
Views: 1819244

Thank you for the reply. I will reply in kind (for all of your posts, of course, not just the most recent one) by next week. In the meantime, I will point out: Yes you are right it has been a month, but what have you contributed in that time? What response have I had from you? However I don't get fr...
by AstraSequi
Sun Mar 18, 2012 11:38 pm
Forum: Cell Biology
Topic: Zygote Homeostasis
Replies: 2
Views: 5003

By "homeostatic," do you mean "exhibits homeostasis"? If so, then yes. All living cells exhibit all 7 requirements - if not, then by definition they are not alive. It's not something that only occurs "from conception" though - conception is merely the time when the zygo...
by AstraSequi
Sun Mar 18, 2012 11:25 pm
Forum: Cell Biology
Topic: what process is needed to create human being
Replies: 4
Views: 3687

Lots of differentiation - specialization of cell types as they go from stem-cell states to their final states as neurons, liver cells, skin cells, etc.
by AstraSequi
Sun Mar 18, 2012 11:06 pm
Forum: Evolution
Topic: Theories - Origin of Life
Replies: 563
Views: 1819244

Re: Theories - Origin of Life

I would call it frustration than being "rattled," thank you - it's now been a month that I've been trying to get you to answer. If you were uncertain about anything, it would only have taken a couple of minutes for you to check, and I was assuming you could do that without me reposting it ...
by AstraSequi
Sun Mar 18, 2012 2:51 am
Forum: Evolution
Topic: Could artificial selection act on fruit flies so quickly?
Replies: 1
Views: 3055

It definitely could, although it depends on how strong the selection is. I assume most of the fruit fly population reproduces in the wild, so the strongest selection factors are probably keeping them optimized for that environment. They might also already be at a maximum for what can be achieved wit...