00:01
We're looking at a genetic cross.
00:03
The parents look like this.
00:08
We want to know the probability of getting offspring with this phenotype.
00:12
Okay, so i will do the probability and show how that works, but we don't need to, because we can look at this and immediately see that this is impossible, because offspring inherit one allele from each parent, and there are not too recessive a -allel for this offspring to inherit.
00:31
So offspring inherit one allele from each parent for each locus, and on parent does not have an a allele to pass on.
00:49
So this is an impossible outcome.
00:55
So without actually having to do any of the maps, we can say the answer is 0%.
01:02
Because ignoring the second two genes, just looking at the first one, this just isn't possible.
01:07
Now, let's do some probability, and we'll see how we would do it if this were a possible example.
01:15
So for each locus, we want to perform a cross separately.
01:21
So for the first locus, the a, we have the homozygous cross with the heterozygous.
01:31
So 50 % of organisms will get two of the dominant, 50 % will get a dominant and a recessive.
01:41
And we do that for each pair.
01:44
So now if we look at b, we have the heterozygous cross, which means 25%, get both of b dominant, 50 % get one of each, 25 % get too recessive.
01:56
And finally, this is a similative of a cross for a, 50 % get that, 50 % get that.
02:05
Okay, so i've used a series of single gene crosses here.
02:12
So you can use planet squares if you want to convert...