00:02
Hi there.
00:03
In this problem, we are looking at a genetic cross between two corn plants, and we are looking at the trait for the color of the kernel in the corn.
00:16
So what we have are two different traits we're looking at.
00:19
There is one trait, which is given the alleles eye, where capital i, capital i, or capital i, little i, both produce kernels that have no color.
00:36
Whereas if you have the homozygous recessive, little i, little i, then the kernels can have color.
00:44
To determine the color, there are alleles at a separate loci, which are known as, let's see, we have big p, big p, or big p, little p.
01:00
Heterazigis condition, both of these will create the phenotype of purple kernels and the genotype little p, little p, the homozygous recessive will create red.
01:17
So what we want to do here is a die hybrid cross.
01:23
They tell us that the parents are both heterozygous for both of these traits.
01:29
So that would mean one parent is big i little i, big p little p, and the other parent is big i little i big p little p.
01:42
Due to indecis dependent assortment, we can get four different pairs of alleles from each of these parents.
01:51
We could get big i with a big p, we could get a little i with a big p, we can get big i with a big p, we can get big i with little p, or we can get little i, little p.
02:02
So that is for both of these parents.
02:05
We would see exactly those same possibilities.
02:11
Remember when gametes are made, made? gametes only have half the genetic material.
02:16
That's why we are only seeing one allele for each of these traits in the offspring.
02:22
So let's go ahead and make a punnet square.
02:25
Since it's a dye hybrid cross, this punnet square needs to be a four by four, meaning we need four rows and four columns.
02:51
And we're going to put one parent across the top.
02:54
So big eye, big p, p, big i, little p, little i, big p, little i, little i, little p, and the other parent down the left hand side.
03:10
But the other parent is also heterozygous, so we're going to get the same four possible combinations.
03:18
I, big p, little i, little i, little p.
03:21
Now it's a matter of filling in our punnet square...