00:02
So in this question, it's asked about a mono -hybridged crust with pea plants.
00:07
One is a purple flower crust with a white flower plant.
00:12
And it also says the f -1 generation plants are purple, and then it asks you to predict the genotype of f -2 generation.
00:21
So let's take a look at the first cross.
00:25
So when we talk about mono -hybrid cross, which means there's only one gene is involved.
00:32
So this gene, we call it p.
00:37
So since there are two different color for pea flowers, one is purple, the other white.
00:42
So this particular gene, p, has two different alleles.
00:46
I use capital p and lower p to represent the different alleles.
00:50
So purple is, in fact, capital p, and white is in fact lower p.
00:56
Okay.
00:56
So if you cross the first parents, capital p and homozygars, with lower p homozygars, so both parents are homozygars, and then you end up having f1 generation because each parents provide one allele, so you end up having f1 generation with a genotype of capital p, lower p, heterozygars, which means the two alleles are different.
01:24
Since f1 generation are all purple, so we know that the purple is dominant and white recessive because the purple dominate the white phenotype.
01:41
Now, so with that in mind, let's go ahead and look at the f2 generation.
01:46
So f2 generation is from the f1.
01:51
F1 parent self -pollinate, so they both have the same genotype, capital p, lower p, heterozygars.
01:57
So when they cross, they produce alleles.
02:01
For each parent, it will produce two type of alleles.
02:04
So you have capital p or lower p.
02:07
So that means when they produce gametes, both alleles have equal chance to be passed down to the gametes...