00:01
Okay, you're going to answer this question.
00:01
Let's talk about inheritance.
00:03
It says the phenotypic ratio of the f1 generation that results from a test cross between a homocygous recessive individual and a heterotogynist individual is 3 to 1.
00:10
So if you have a heterocygoyles individual and you cross this individual with a homocybozygose recessive, then you're going to get here heterocygotechot, heterocyg, heterocycote.
00:20
So you have a phenotypic ratio of the ad they are telling you, well, they are not telling you a genotype ratio, oh, i'm sorry, they are telling you the phenotype ratio.
00:31
So the phenotype here is going to be 2 to 2 because these two are going to call for the dominant phenotype and this two are going to call for the recessive phenotype.
00:39
So your ratio is going to be 2 to 2 particularly.
00:43
Okay, so this option is going to be false.
00:49
Then you have the next question that says following is face, a human cell would have how many pairs of sister chromatids and individual dna molecules.
00:59
So remember that normally this is one chromosome.
01:02
Before dna replication or before the s phase.
01:05
After the s phase you're going to have this, where your chromosome is going to have one chromatid here and another sister chromatid here.
01:14
So per chromosome, you're going to have two sister chromatins.
01:17
And if you're...
01:18
It is talking about humans, humans normally have 46 chromosomes.
01:23
So they are going to have 92 sister chromatics.
01:29
And they are asking you for how many pairs of sister chromatics? so, you have one pair per chromosome.
01:40
This is one chromosome and you have one pair of sister chromatis.
01:44
So practically, if you have 46 chromosomes, then you're going to have 46 pairs of sister chromatids.
01:50
And then it says an individual dna molecules, well, the dna molecules that you're going to have are, this is one and this is two.
01:55
So you have two per chromosome.
01:57
As you have 46 chromosomes, then you're going to have 92 the individual dna molecules.
02:01
So the answer is going to be 46 pairs of crystal chromatids and 92 individual dna molecules...