Sexual Evolution: From X to Y
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- Опубликовано: 31 мар 2010
- The presence of the Y chromosome triggers a human embryo to become male. Dr. David Page describes how the Y chromosome was once very much like every other gene-filled chromosome, but in the course of vertebrate evolution has lost almost every function except making males.
Very helpful video,, thanks for that
facts are the first basic element toward understanding, but what most important is the idea constructing the rational and dismissing what is irrational, and given what's observed helps us establish hypothesis that are verified either by generalizations, eliminations, contradictions, cross validation, or tests
What is going on in this discussion? And so thanks for posting this vid!
u'r half correct here. One, is that the Y chromosome is present since conception, hence we cant't call it female that develops into a male or default female. Two, it takes two X chromosome to make a female "as in healthy male XY and female XX". To call the embryo asexual is to call XY asexual or Y isn't a sex hormone which is incorrect. continued...
Ironically toward the end a student asked about gene splicing for the daz gene and the professor said it was quite some time off. here in 2013 it is being done in England; 3 parental gene pools spliced to make one child.
It must be noted that the process of developping sexual corresponding organs the following: 6 weeks for male testicles, 12 weeks for ovaries, are we therefore should call the female XX quasi male just because she was asexual for longer period
Can the "X" and /or "Y" from a human be replaced with sex chromosomes from an animal? And still produce a child?
Just to clarify your question, humans are still animals - but no the chromosomes for humans are very specific to humans. Replacing the X or Y chromosome with an X or Y chromosome from a different species will not produce a child.
let me correct the word i misued "hormone",chromosome obviously i was thinking in terms of the androgens cocktail it helps establish in the male body.and again, i 'll correct you, for mamals, the default sex IS NOT A FEMALE, it's fallacy. the default sex is an asexual template..Y chrom is present since conception, to say the dfault sex is female entails that female has Y chromosome, which isn't the case. the X is a template either enhanced by another X or a Y. Y isn't present in females "normal"
u know in my math and physics department we discretely make fun of biology and how it lost standards since the introduction of many scientists wanna be "mass recruit of women "any woman" in detriment to capable males". and now biology has to recruit engineers and mathematicians to help them build computational models for biological elements and dynamic behavior to make it easier for them to interpret observed data.
Does each sperm or egg carry the same 32 chromosomes? Does it matter which sperm reaches the egg or will the child be the same?
Humans have a total of 46 chromosomes, but both the eggs and sperm of humans are haploid, meaning that they only contain one set of each chromosome, resulting in each egg and sperm only having 23 chromosomes. With that being said, each egg is individually distinct from other eggs and each sperm distinct from other sperm because of a process called recombination in which genes are mixed and shuffled. They are also subject to mutations, which can subtly or drastically change the genes in each sperm or egg.
continued; two u retreated to ad-hominems, and three u claimed that i said that mullarian structures are the derterminant of sex/gender where as what i said they're not causative, they're not the reason why sex is determined. these are part of the structures like any other organ. the presence and proper development of an XY will lead to male all the time "keyword: proper development", variations will lead to distrubance of the development and hence implicit or explicit dismorphism
the reason why we didn't have them from the begining, that goes back to very complicated mathematical formula governed by fractals and golden ratio, that is to say, development starts from the kernet up the extremeties, the fact that u didn't witness from the begining any genitalias is obvious due to the way all life forms develop. do u see ur legs from the begining, No, u see the kernel,but the genetic material have XY from the begining. wrap ur head around it. this is mathematician perspective
u said "..your argument can only be true if the fertilized egg was aware of the chromosomes it possessed.",what does this even mean ? biological structure are subject to chemical reactions, proper functioning render proper operations, otherwise it's abnormal.we are talking about Y chromosome, if it exists since the beginning, it is male up to the point where development is disrupted by random event or mutation. If it's X it's a female. if neither, it's template "turner" not female sensu stricto
I'd thought u'd be better than this...instead of throwing ad-hominems, u at least take full heart the fact i told and keep the conclusion to your self. There is a trivial saying that floated around between student when i was in grad school and it holds true that goes like " if u eliminate all the possibilties, what ever u'r left with no matter how improbable, must be the truth"
u made a fallacy by saying first in the absence of Y it defaults to female "not necessarily" it is referred to as female "turner dusmorphism" only because the individual has an female chromosome, but she's not medically a female "XX". then u go hasty by saying "if anythingit's female until...", but Y chromosome is present, u said "in the absence" so it's not a female because it won't default to it, So either XY is female "incorrect" or asexual "correct".
16:35 This is where it gets good. The Y-chromosome is asexual. It is produced as a "clone" through one lineage.
Let me wrap it for you...my point is summarizable to the following set of premises:
Y is male chromosone
XY is male as is and observed
XY is female, based on what u asserted that XY starts as female
Y is female chromosome "if female has it at any stage"
But Y is not present in females
Hence Y chromosome is not female
Therefore XY is not female
Can x turn to y one day💔
Think about something, if a female only was at the begining, it means two copulated of the same kind but one had to have a mechanism that allow one to deliver one chromosome to the other, except that they are similar, if it was only female self replicating, it means they're copies of the original, at what point and how two similar xx have different sexual organs. The whole idea is flawed.
Midwifery and women's sexuality educator Whapio Dianne Bartlett writes, "At all times, women have the complete components of genetic material in their eggs to create life." Humans have 46 chromosomes, during conception 23 of the women's chromosomes combine with 23 of a man's chromosomes - however women actually have 46 chromosomes completely in their eggs at all times! When they conceive with a man the "extra" 23 chromosomes get put aside in a pocket and absorbed - but this poses a question as to what the purpose of these extra chromosomes are for in biology - could it be the ancient art of parthenogenesis. Parthenogenisis is womans ability to self conceive, we can still do it. The X chromosome is older , women were here thousands of years b4 men and yes we self conceived and had only daughters due to the XX chromosome. Science knows this they are covering this up. The y chromosome is the X but it's missing dna. So basically men came later and are just lesser women....
+Amia Clairsentient
By lesser, you mean stronger, faster, smarter, and hardier?
If u define female...as female looking. yeah, but in the gender characterization, they're incomplete females...or not sexually functioning female...i'm speaking from the logical sense. i'm not speaking in subjective term of how gender is interpreted socially. Gender in its core is binary...a male or female, anything else is disrupted normal development, hence the deficiency in sexual function.
answer this have u found a full operational male "sexual function since the subject is about sexual genetics" with an XX. NO. have u found a full operational female with XY, NO....XY is male and XX is female....in between is random mutations...much like predisposition to crohn disease or other immunological disorders
u didn't have serious questions, u had irrelevant questions coming from unsubstantiated assertions and fallacies, u have to depart from correct ground, in order to qualify your question as legitimate. I don't take any question seriously unless if it is solid in terms of its premises. Not that find it explicitly posed anyway
3 rd sentence should say "when they are really conpensating for not being born *fertile*"
let me repeat it for u..in the state of affairs, babies are born either boy or girl..the rest is abnormal development, boy or girl are the product of their corresponding genetic material in regards to sex it is XY or XX. U telling me u'r not logical without explicitely demonstrating where logic failed, is equal to me saying to u u'r black but u'r caucasian. Genitalias are the expression of genetic materials, when proper development occur, u have either a male or a female
u said i'm not up to date with studies in this subject, well my friend i couldn't describe to you how appalling to see many fallacies/interpretations of resutls in biological field. As mathematician i see errors in assertions...and certainly i see wrong interpretations. If every healthy Male has Y chromosome, then baby who has XY is male from the start, same for female. X chromosomed individuales are templates because they do not have precursors of female characteristics. continued
Well, in the absence of a Y chromosome the embryo will "default" to female; so, if anything, it's female until the testes develop. Really, though, the embryo is asexual until a couple of months in.
the fact that there are infertile females is non--sequitur, those are also driven by some random variation that led to improper development of associated organ functions. you buddy, has shown three times at this point u'r not capable of holding credible, serious discussion from critical point of view. one u claimed Turner give birth naturally, ...continued
Why...do u say this stuff, because i logically demonstrated to you that what you know or what they fed is incorrect and incoherent.....the rational mind no matter what is the one that has the key to peace of mind, if u want to live in delusions ...that's ur life
men are done. even here the women are answering all the questions. we are going the way of the whiptail.
Yes see but that proves that Y came from X. Y factioned off and then became this floating static parasite thing.
i'm afraid my friend u'r clinging to an idea just because it suits ur taste buds for one reason or another. u want knoweldge u got face the irregularities in the horseshit that is ample in biology, psychology, social sciences, and even neurology recently.
back to Adam? this guy does not understand science