13. Mendelian Genetics
Was this helpful?
in this video, we're going to continue to talk about Gregor Mendel's experiments. And so Gregor Mendel used two different types of fertilization or gaming fusion in his experiments, using either just one or two parent organisms. Now the very first type of fertilization that Gregor Mendel used in his experiments is self fertilization, and as its name implies, the organism is going to be fertilizing itself. And so it on Lee involves one parent organism, and so self fertilization is when Gregor Mendel would apply pollen from a male organ to a female organ on the same plant. And so again, this is only going to involve one parent organism, and the organism would be fertilizing itself, therefore calling itself fertilization. Now, the second type of fertilization that Gregor Mendel used in his experiments is cross fertilization and cross fertilization, unlike self fertilization, requires two parent organisms. And there's going to be a cross of gametes between these two uh, organisms. And so, in cross fertilization, Gregor Mendel would cross pollen or apply pollen from the male organ toe, a female organ on different plants. And so again, this is going to require two parent organisms. And so if we take a look at our example down below, we can better distinguish between self fertilization and cross fertilization. And so over here on the left hand side noticed that we're only showing you one single plant here. And so this is going to be self fertilization when you can take pollen from the male organ and transfer it to the female organ on the same exact plant. And so that would be self fertilization. Now, over here on the right, notice that we're showing you cross fertilization because we're showing you two plants and noticed that pollen from the male organ of one plant is being transferred to the female organ on a different plant. And so this is called cross fertilization now moving forward in our course. When you see this arrow going across the two different plants, that's going to represent cross fertilization. And when you see arrows that loop back up onto itself, that's going to represent self fertilization and so moving forward in our course. We'll talk Maura about Gregor Mendel's self fertilization experiments and his cross fertilization experiments. So I'll see you all in our next video
Self-Fertilization Experiment: True-Breeding vs. Hybrid Plants
Was this helpful?
In this video, we're going to introduce Gregor Mendel's self fertilization experiment, which helped him distinguished between true breeding and hybrid plants. And so true breeding is highly linked to Ho Mose ICUs plants and Gregor Mendel called true breeding plants, plants that would self fertilized and produce offspring with the same phenotype as the original parent. Now hybrids, on the other hand, are highly linked to hetero zegas organisms and Gregor Mendel called hybrid plants. Plants that, upon self fertilization would produce offspring with mixed phan, a types that are not always the same as the original parent. And so mono hybrids eyes just a term that refers to organisms that air hetero zegas for just one specific trait or gene. And that's because the root mono is a route that means one. And so again, mono hybrids are hetero zegas for one specific trait or gene. So if we take a look at our image down below, we can better distinguish between true breeding pea plants and hybrid pea plants. And so notice over here on the left. What we're showing you are true breeding pea plants and so notice that we have over here on the left a homo Zegas dominant plant that has two dominant alleles to capital wise and notice that this homicide is dominant plant is being self fertilized, meaning that it is fertilizing itself. And so in that scenario, we basically have, uh, Hamas, I guess. Dominant being crossed with the same exact Hamas, I guess. Dominant. So we have to capital wise as the game meats across the top and the sides of our planet square. And of course, this creates, uh, organisms, offspring that have the same exact genotype and phenotype as the original parent. And so this is why all of the offspring are going to be yellow. And that means that this is part of true breeding. Now, over here on the right hand side of true breeding, we're showing you a Hamas, I guess Recess it plant that is green. And, uh, notice that this home is I guess recessive plant is being self fertilized. So we're having ah, Hamas, I guess. Recessive cross with another homos, I guess. Recess of which is itself. And of course, that's going to create offspring that are all homo zegas process of all green offspring. And all of the offspring have the same phenotype as the original parent, which means that this is another example of true breeding. However, what Gregor Mendel noticed is that sometimes when he crossed yellow plants that they did not create true breeding results. And so over here, notice that this is showing the hybrid plants and the hybrid plants. Turns out our hetero zegas, meaning that they have one dominant Elio and one recess of a Leo. And even though they have a recess of Alil, you can't tell just by visually looking at them because the recess of Lille is being masked or hidden by the dominant Eliel. And so this plant appears yellow just as the homos. I guess dominant one would appear yellow. However, when you self fertilized this hybrid plant over here, what you get our results that are different than the true breeding results and what you end up getting. Of course, when you fill in this pundit square, you get the homeless, I guess dominant here you get a hetero zegas here, you get another hetero zegas here and of course you get a homos, I guess recess it in this last box. And so what you get is a mixture of offspring with the hybrids. And that's what we're showing you down here is that some of the offspring are going to be green, so you get a mixture of offspring, and that is how these hybrids were identified. And so Mendel's discoveries, using self fertilization intrigued him. He became fascinated by this, So what he began to do is cross fertilization experiments using pea plants where he would again take pollen from one male plant and transfer that pollen thio pollinate or fertilize another, uh, plant the female organ of a different plan. And so this year concludes our introduction to Gregor Mendel self fertilization experiments and how he was able to distinguish between true breeding plants that produce organisms that have the same exact phenotype as the parent from hybrid plants that created a mixture of offspring upon self fertilization. So we'll be able to get some practice with this as we move forward in our course, and then we'll talk about cross fertilization experiments. So I'll see you guys there
Cross-Fertilization Experiment: Dominant vs. Recessive Alleles
Was this helpful?
In this video, we're going to introduce Gregor Mendel's cross fertilization experiment, which helped him distinguish between the dominant and the recess of a Leal's. And so Gregor Mendel discovered dominant and recessive traits when he cross fertilized yellow pea plants with green pea plants. And so, when analyzing the offspring of crossing yellow and green pea plants, he noticed that he always found yellow peas. In every scenario that he crossed the yellow with green pea plants, he would always find yellow. And so this told him that the yellow color must be the dominant trait if it's always showing up in every scenario that he crosses a yellow and a green pea plant. But then Gregor Mendel also realized that sometimes Gregor Mendel would find a mixture of FINA types where he would find yellow and green offspring. But Gregor Mendel never found all green offspring when he crossed yellow and green pea plants. So this told him the fact that he never got all green offspring, that the green trait must be the recess it trait now, once again, sometimes when Mendel found a mixture of FINA types, um, that gave Mendel a clue that some of the yellow pea plants are going to be hetero. Zico's on that. They're going to have one copy of the illegal for each of these traits. And so, if we take a look at our image, down below will be able to see uh, Gregor Mendel's cross fertilization experiments. And over here on the left hand side, he's crossing a homo Zegas dominant yellow plant with a homo Xigris Recess Ivo Green plant. And, of course, when you set up the the Pundits Square for this, you'll put the gametes of one parent on one side of the square. So we'll put the capital wise over here and you put the game. It's of the other parent on the top of the square, so we'll put the lower case wise here at the top. And, of course, when you complete the Pundits Square, which will realize here is that you're gonna have a capital Y and a lower case, why? And that will be the same for all four of the squares in the pundit square. And so all of them are going to be hetero zygotes and hetero zygotes all come out yellow. And so when Gregor Mendel did these cross fertilization experiments crossing yellow with green. Ah, lot of times he would just get all yellow offspring. But then sometimes when he crossed yellow with green pea plants, he wouldn't get all yellow offspring on. This is because it turns out that the yellow plants that he was crossing were hybrids or hetero zegas. And, uh, the homos, August recess of green plants were still homo zegas, recessive. And so, of course, when you fill out the pundits square here, what you get is the capital. Why is going to be brought all the way across the lower case? Why here will be filled in and then down below. Here you have all lower case wise. And so when he crossed a hetero zegas yellow plant with a Hamas, I guess recess of green Plant. What he saw was a mixture of offspring. He would get 50% yellow and 50% green. And so, once again, um, the fact that he never got all green when he crossed yellow and green pea plants told him that the green must be the recess. It p colored. And of course, the fact that he always got yellow and no matter how he crossed yellow with Green told him that the yellow color must be the dominant p color. And again, um, he was able to get a clue that hetero zig it's existed when he saw this mixture of offspring. And so this year concludes our introduction to Gregor Mendel's cross fertilization experiments, and we'll be able to get some practice applying the concepts that we've learned as we move forward in our course, So I'll see you all in our next video.
Mendel crossed a pea plant with yellow peas with a pea plant with green peas. All of the offspring created from this cross has yellow peas. What must be true about the parent plants of this cross for this to occur?
The parent with green peas was heterozygous for pea color.
The parent with green peas was homozygous recessive for pea color.
The parent with yellow peas was heterozygous for pea color.
The parent with yellow peas was homozygous dominant for pea color.
A and C.
B and D.
You cross a pea plant with yellow peas (Yy) and a pea plant with green peas. How many unique genotypes are possible for pea color in the offspring? How many unique phenotypes are possible for pea color in the offspring?
2 unique genotypes; 2 unique phenotypes.
3 unique genotypes; 2 unique phenotypes.
2 unique genotypes; 1 unique phenotype.
1 unique genotype; 1 unique phenotype.
Generations of Mendel’s Plants
Was this helpful?
in this video, we're going to talk about the generations of Mendel's plants, and so Gregor Mendel standardized the naming system of generations to track inheritance patterns. And so really, there are three generations that you all should be familiar with, and the very first generation is the parental generation, and the parental generation is commonly abbreviated as the P generation. And so this, of course, is going to be the original set of individual plants that are made it or the parents, if you will. Now the second generation that you all should know is the first filial generation or, in other words, the F one generation. And so the first filial generation or the F one generation is going to be the offspring of the P generation. And of course, the word filial is a word that's related to child. And so, of course, this is going to be the Children of the parental generation. And then, of course, last but not least, here we have the second filial generation or the F two generation, and this is going to be the offspring of the F one generation plants. And so let's take a look at our image down below to get a better idea of these generations. And so notice Here in our first block, we're showing you the P generation, which is going to be the original set of parents that are made it. And so here, what we have is a homo zegas dominant pea plant being crossed. What they homos, I guess. Recess, Ivo Pea plant. And so, of course, when you set up their game meats on a pundit square like what you see here, you set up their game. It's on the planet square and you fill in the pundit square What? You're going to get our hetero zegas individuals in each of these pun. It squares in each of these squares. It's representing a hetero Zika's Gina type. And so the individuals that are inside of this pundit square represent the F one generation. And so that leads us straight down to this next part Here. Uh, the F one generation, of course, is gonna be the first filial generation the Children of the parental generation. And of course, because these offspring, these Children of the parental generation, are all hetero zygotes. Of course, we're looking at Hetero Z gets here And so here we could either cross fertilize a single heterosexual, or I'm sorry, self fertilized, a single heterocyclic, or we could cross fertilized to hetero zegas. Either way, we're going to have the hetero Zegas Ah, wheels of the game. It's across the top. And when we fill this in, what we will have is, uh, this right here we will have one ho mosaic is dominant, uh, to hetero zegas and one homo zegas recessive. And these are the possibilities of the offspring. So these squares within here represent the F two generation, and that leads us to the next us. Where that we have down here, the F two generation is going to be a Z. You can see here, uh, three of the four possibilities are going to be yellow, so you can see these three possibilities here are yellow. And one of the possibilities of the F two generation here would be green. And so the generations are just referred to as p generation F one generation or F two generation. And so this year concludes our introduction to the generations of Mendel's plants, the P F one and F two generations, and we'll be able to get some practice applying this as we move forward in our course. So I'll see you all in our next video.
In the study of genetics the offspring of the parental generation is referred to as the:
Additional resources for Mendel's Experiments
PRACTICE PROBLEMS AND ACTIVITIES (1)