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和大家分享一款连杆设计器 linkage, 这一个版本是三点一六点一四,汉化版的 这一个软件自带许多视力,我们随便点开一个看一下,看一下这一个挖掘机的挖掘币,我们点击一下运行按钮,可以看到连杆的运行机制, 我们也可以手动地去拖拽它的控制器,让相应的油缸产生适当的运动。 我们再来看一个另外的视力,这一个椭圆规我们运行一下, 可以看到他捕捉了两条椭圆曲线。 这一个软件自带的说明书是英文版本的,而且里面注解的也不是很清楚, 所以我花了一点时间做了汉化版的教程,基本上是参考原英文教程,做了一些详细的注解。 下载地址我稍后分享在评论区,欢迎大家下载研究。


hi, i'm kelly, today we're gonna learn about biology today we're learning about sex linkage so we've been learning a lot about crumsomes and well, you could learn we've been learning a lot about cromsomes and also things and well, today we're gonna see what determines sex so we've been looking at the poonie square and all those things how jeans are passed along from parent to parent how you got to your dad's nose or your mother's face or something something but uh and that's what we're gonna see today we're gonna see what determines sex as we know there are two sexes female and male males have an x and y chrome zone and females have an x to an x but there's a sing uh y chrome zones they have their their crumsoms are slightly smaller humans have forty six crumsoms and if you split that in like a total half, you get twenty three crumsoms that would make a pair right a pair of twenty three so the last the last two chrome zones are the last pair of chrome zones of that forty six chrome zones that would be the sex chrome zones and that determines your sex the sex chrome zones there an x and y of your mail and it's an xx if you're female, so this is how determines we're using a pun and square you can also use the pun and square to determine sex actually and it's all very like straight out it's all very straight out it's the it's equal i mean if having a boy or a girl, it's all equal actually sew intestines of male x, y for males and sewing over a female x, x the egg will bind to either an x or y cromso and any of them can get to it every sperm contains a y or an x and well, we know that whichever sperm gets to the egg first will get it fertilized and then we'll have to see what kind of chrome zone what kind of chrome zone was in that was in that sperm so rabbit the diagram shows how sex is inherited all the females x contain an x from them have to make sperm contain an x chrome zone and the other half contain a y chrome zone okay, it will fuse with an x or a y as i said and that will determine the sex of the child linkage we've learned about a linkage before basically it's where genes are located on the same crumbsomes there are two totally different genes let's say the sex crumsomes this can happen to sex linkage it will happen where the six chrome zone contains like factors determining like eye color or any other sort of determine or any other sort of g so that's how it works this is called sex linkage we've learned about normal linkage where two different two different genes are located on one chrome zone and these jeans determined totally different things but they're all the same chrome zone and same same for sex linkage one half of that chrome zone determine six other half detains determines something else and i don't know what but sometimes that happens not all the time sometimes it's just sex determiner only there sex one engage occurs when jeans are carried on the sex chromosomes, these jeans may have nothing to do with sex determination they just happen to be carried on the x or y chromosomes a y chrome zone is a bit like an x chrome zone but we have a bit missing yeah sort of if you take like this half or this half of the chrome of this x away, you get a y right and once you get that wides like the same of this so why chromosomes are smaller? because they contain well less bits it's very yeah we'll talk about other things so this is it this part actually, this is a better picture as the wiper room's only smaller it carries fewer adults x chrome zone y chrome zone it looks very much alike only the y chrome zone has a part snipped off if we added this part up, then it would be an x chrome zone right so therefore x chrome zones are bigger they contain more genes than the y chrome zone this part is missing from the y chrome zone and now we're going to talk about color vision we know about color blindness and well, if you've heard of it, then you know that males they are more likely to be color blind if you've ever met color blind people in your life, i bet that more of them were male than female because well, because of the chromosomes we're gonna talk about that right now this is a prudent square i guess we have it this c it represents the color bind is it's a recessive one because it's a lower casey and this is an upper casey representing a dominant one this person is a normal sided female and this one is a color blind male okay, normal sided damage will mix and you get oh and there's only like one y chrome zone this y that part that was snipped off that was in charge of carrying like another another chronsom, another gene determining how many colors you see so that part was snipped off so now the y chrome zone cannot carry any jeans for color vision and now the x chrome zone has to do it all and males only have one x chrome zone so they only have like one jean for color vision and wild females usually have two because xx this is the pun and square x and c x low c okay ratio a one female carrier one normal sided meal that is a ratio here it is norm these are normal sided males and these are carrier females cause well they have a lower case c that lower case c is a carrier er the sort of color blindness is actually a recessive g so that's why it's a little c dominate one they're not and here we have it this is they are carriers the second x has a recessive c for the color blindness this one cannot have it because it's a y crumbs on and i guess you know why there is a defective recessive adult of the color researching, which can lead to color lineness particularly of red and green light okay, this is c that is the adl for normal color fishing, which you find in this normal sided female cc and this recessive c adl that is for the color blind is found in this color blind mail is why can't carry anything? so it can't stop it with a dominant normal gene so males only require one gene of recessive they only require one gene of color blindness to activate the color blindness while females will need two so that's why males are more likely to get this kind of stuff what happens? if we cross a normal sided female with a colorblind male wow, it said here this is a colorblind male normal sided female this is what we get a one to one ratio these are let's see if they had four children, two girls, two boys and well one of the boys they are fine they are elsie, noncolor, but and females are carriers of color blindness but they all of these children are not color blinds these are carriers, these are not carriers so that's it but we're gonna see more by the way red green color blindness this is like the most common form of color blindness where you can't see green or red red looks brown and green looks yellow or something but you can't see these two colors if you if you have red green color blind okay uh what happens if we cross a normal sided female with a color blind male, it's said here uh a normal sided female it already said here but we're gonna see more female with two adults for color vision male with one adult for color vision this is what it means the it could the male would have had like two adults for color vision if this chrome zone were bigger, so they are more likely to be color blind all of the spring are normal sighted the females have the adult for color blindness on one of their ex chrome zones that means if they come together if they cross with another color blind mail, it's likely that they'll get color blind children as well okay now let's cross a normal sided male with a carrier female this is a normal sided male with a carrier female normal sided this is like this is like the this is like the f one generation this is like the f two generation because you see the children, they are exactly the same to what we are frosting but let's just do it and you get get a color blind male and well, because it is a carrier female you see every time if you got a carrier female that comes together with a normal sighted male no matter what you do? there will always be a color blind male so no matter what you do the child if it's male, it will be color blind well if you had four children, so if there was one color blinded children in that family, then it would be it would definitely be a boy no doubt all of the offspring are normal sighted the females have the adele for color blindness on one of their x chrome zones we say that they are carriers they have the color blind adele but do not show it in their final type now let's cross a normal sighted male with a carrier female there is a wonderful chance that the carrier female will pass on the color blind adult to one of her children and it will always be a boy says here always be a boy because well the boy has like no way to it has no way to push away the recessive adult because it can only contain because y problems on can't contain like a dominant gene or something to push the recessive adult away then the recessive adult will take over it will take over and it will and the gene and the child will become color blind and that's it that's all we have for sex lungage it describes how to like see if your child will be male or female, but actually, there is no way because after you've seen the poonie square saying it's totally after we've seen the punet's question we know that it's totally random sex and stuff you know determine a child sex is hard it's total it's totally random unless you're like keeping track of all the sperm and stuff so it's random it's really random this is uh these are like other things about color blindness, but color blindness is easier to predict if you know the circumstances, the chromosomes of the two parents, you can predict you can pretty much predict what their children will be like will they be color blind or not and well most of the time they won't be because color blind people are not that many but still there are and that's all we have for sex linkage hope you enjoyed the lesson if you did smash like goodbye。