00:01
Okay, i want to answer this question we're also talking about myiosis, okay? remember that myosis starts with a deploy cell.
00:07
They're going to divide into two upright cells.
00:10
This occurs in myosis world.
00:12
Okay.
00:13
One important event here in myosis one is that during prophys 1, a project called crossing over occurs.
00:21
Okay, for example, this is one of your homologous chromosome, and this is another chromosome.
00:27
Both, remember that both are homologous chromosomes.
00:31
During crossing over, one segment here, for example, is going to exchange by this segment here.
00:36
So you're going to have this, and you're going to have this.
00:43
Okay? so this is what happens in crossing over.
00:46
The question number one says, which statement that below is true? option a says, cursing over shuffles genes between non -omologous chromosomes, and this is false.
00:56
Okay? let's say it here, it is false because it occurred between homologous chromosomes.
01:00
Like in this case.
01:03
Option b says during myosis, sales arrange their alleles so that beneficial are passed on together.
01:09
And this is also false, okay? because all of that is independent, it's random or it's a random process.
01:15
The cell is not going to select beneficial alleleys and pass on together.
01:21
So that beneficial elites are passed on together.
01:24
That doesn't happen.
01:25
Okay, because if that would happen, then imagine there were, there wouldn't be generated, there wouldn't be genetic diseases that are inherited from parents.
01:34
Then option c says without crossing over, offering would be genetically identical to parents.
01:40
And this is false because it is correct that it is going to, it is going to be important in order to create genetic diversity.
01:51
But there are other processes that are going to also participate in the genetic diversity.
01:56
For example, when cells or when chromosomes are independent assorted and also when the ovum fertilizes for a random ovum produced by myosis fertilizes a random sperm produced by myosis in the father okay so all of that is going to contribute to genetic diversity so a cursing over contribute contribute to that but it is not going to be the only process that contributes for genetic diversity option this is new combinations of a lease arise from the random events of course over independent assortment in mutation and this is correct okay this is correct and this is the answer for this question the second question says what a statement below is true of the spindle during mitosis and myosis option a is the spindle always separates sister chromatids during anaphrase and this is false okay because during myosis one for example during myiosis one you're going to have your chromosomes in this way okay you know that during mytosis you're going to have your chromosomes in this way right during mytosis but during myiosis but during myelosis but during my they are going to be like this, it means they are going to form tetrads because you have one chromatid, another chromatic, another chromatic, another you have practically here for chromatids.
03:09
So this is a titrat.
03:10
So this is not true because it says that always separates sister chromatist during anapase...