I know that a sperm is a single cell but how does that cell come into existence, is there a process where another cell changes into a sperm cell? Having just one cell makes it hard to comprehend.
I’ve not a clue but that is a fascinating question. Is it alive? If so, at what point did it become alive? And how?
I was going to explain the path from stem cell to spermatozoa but the Wiki article posted by @Chronos does it much better.
Put much more simply, dedicated cells divide by a process called meiosis from a 46,XY cell that is in most of a man’s cells, into four gametes, two 23,X and two 23,Y.
In ovaries, those cells also divide in a similar fashion but the original ova do not multiply after birth, or even before. The 23,X ovum will also have polar bodies, which, if fertilized, give rise to a hydatidiform mole, which is an abnormal placenta with no fetus. Thankfully, this is very rare.
That was a very good article, explained many of my next questions. I will give the reasons I am asking. I have a curiosity about Epi genetics, I tend to believe that somehow our neuro chemicals and hormones play a part in sperm development. I was trying to imagine if there were any human examples of this that might somehow be explored over multiple generations. There might be quite a few examples in the arts but the only physical eample I could think of was surfing. We might have 4 generations of surfers floating around that were conceived of during their surfing days It would be cool to study them.
Are you referring to epigenetics?
I think so but it might not be the right term for the aspect I am looking at.
It is how I know it is spelled. Could you perhaps link to how you are using the term?
Epigenetics is 100% real.
The OP seems to be talking of something more Lysenko-esque (read as “nonsense”), where the act of e.g. surfing while of reproductive years produces offspring more likely to be surfing enthusiasts themselves.
People often do their parent’s occupations or share their parent’s enthusiasms. I and one of my brothers have/had the same occupation my father had. Etc.
That doesn’t require (epi-)genetic alteration; it requires growing up in that milieu and hence socialization directed in that direction. It’s no more hereditary or epigenetic than the amazing coincidence that I speak the same language my parents did.
For the record, HBDC has had at least 2 threads on epigenetics and/or sperm, with minimal reference to commonly accepted terms and definitions.
Along with much additional debate in their Pit thread. As this is FQ, I do not comment on those other threads, but since there had been requests for HBDC to define how his usage differed from those of credentialed professionals in the field, I felt the existing references to his views may be helpful.
The specific interest I have would pertain more to things like locomotion, walking swimming, flying running climbing etc. Anything and everything we do does generate a unique set of chemicals during the process. Neuro chemicals are likely a universal language of sorts if we were able to read them. During the formation of sperm it is bathed in these chemicals not blood. We produce about 300,000,000 per day of which only 100,000,000 survive. Who is to say that our neuro chemicals don’t play a part in which survive? There is a lot of room for slight modifications with the large numbers involved.
And this term “Epi genetics”-where is it defined and where does it come from?
Someone said in another thread that’s the word I needed so I used it. If you are referring to my spelling it was just a mistake.