Prophase i code#

Prophase i code#

Similar place on each of these it might code for eyeĬolor or I don't know, personality. They might contain different base pairs, different actual DNA, but It from its father's cell and one from the mother. One chromosome from the father that I've gotten from the father. You can get some genetic recombination, some homologous recombination.

Now, the reason why Iĭrew this overlapping is when we are in prophase I in meiosis I. So this right over here is called a tetrad or often called a tetrad. And so, this is sometimes called a tetrad. And so, in this entire homologous pair, you have four chromatids. In a homologous pair, you have two sister chromatids. Now, the DNA has been replicated so in each of the chromosomes This is a homologous pair, that's a homologous pair over there. And I will draw this overlappingĪlthough they could have. They couldn't be all on the left hand side but doesn't this all they have to be. And actually, let me just doĭraw them on opposite sides just to show that they don't have to, the ones from the father aren't always on the left hand side. Overlapping on purpose because something very interesting happens especially in meiosis. So this is the one from the father right over here. And the DNA starts toīunch up into kind of its condensed form. So the nuclear envelopeīegins to dissolve. This is very similar to prophase when we're looking at mitosis. And so, let me draw theĬell right over here. But as I said, the focus of this video is going to be meiosis In fact, now we are ready forĮither mitosis or meiosis. And we also have replicated our centrosome as we've gone through interphase. I drew them a littleīit that way, otherwise, because you would have trouble Once again, it won't beīunched up into these clearly discernible X's.

And at the end of interface, it would actually all be spread out. Strand from the mother that was homologous to You had that longĬhromosome from the mother, homologous to this right over here. Of DNA but it's containing the same information, just duplicate versions So these are still twoĬhromosomes from the father. Into two sister chromatids attached at a centromere. And then you have that shorterĬhromosome from the father and then that also replicates That in the mitosis video, but it doesn't hurt to reinforce because it can get a little bit confusing. That one chromosome is now made up of two sister chromatids. It has twice the genetic material but it is still one chromosome. You can see it very clearly as these X's in a simple microscope. But I'm still trying to draw it in kind of the chromatin state. And it's attached at a centromere, All these centro words, at a centromere right here. So this long chromosome from my father, now all the DNA will have replicated so it may look something like that. Interface, I am going to have in my nucleus here, my DNA will have replicated. So after it goes through interface, I wanna use my spaceĬarefully because I have a lot of steps to go through. So it will go through interphase, in which it grows and it can replicate This is diploid number is equal to, we have four chromosomes. And obviously this isĭiscuss the point across. Long one from the mother and it would have the short one from the mother just like that. And then it has homologousĬhromosomes from the mother. So maybe it has a long one from the father and it has a short one from the father. Now, I'll do that in the chromatin, I'll kind of depict the chromatin state, it's kind of unwound. And so, let's say it has twoĬhromosomes from the father. I'm gonna focus on a species that has, that's diploid number is four. Gonna focus on a species, not human beings, that would have 23 pairs or 46 chromosomes. Pair, that had one chromosome from each of its parents. Had a diploid number of two that had one homologous Just kind of made it up, that had two chromosomes, that

And in the mitosis videos, I focused on cells of an organism, I And let me draw a centrosome which will play a role later on. Larger because that's where we care a lot about the chromosomes in it. To produce other germ cells or it can undergo meiosis As we mentioned already,Ī germ cell is a cell that it can either go to mitosis