00:01
Hi there, everybody.
00:02
Today we're talking about some interesting aspects of mitosis and kind of about the specific problems that is dealing with the processes of the cells.
00:18
And we're talking overall here about animal development, right? so we're going to think about this in the realms of development.
00:25
So that's why this matters.
00:27
And when we look at any question, we're going to think what were the text? book makers, what was somebody in this paper that's postulating this question? what is their purpose here? and since we're looking at an overall arching theme in this chapter of development and animal development specifically, we're going to use that to frame our decision making here.
00:51
We're not going to just look at these by themselves.
00:53
We're going to take that and we're going to figure out what exactly is referring this question wanting out of us.
01:01
What is it wanting us to learn? so we're trying to figure out what this process is, okay, that they've been talking about having to deal with cells.
01:16
They're undergoing mitosis, but they're not having a corresponding increase in cytoplasm.
01:49
So this is the important factor here.
01:52
So this is kind of like a negative question.
01:53
So we're looking for all of the rest of these, okay? we have five options.
01:58
All of the rest of them are going to have an increase in their cytoplasm.
02:02
There is, i mean, there is going to be an increase in cytoplasm in basically what's going on here.
02:10
So we're going to first look at a, which is polarity.
02:18
So when we're thinking about polarity as a process, we're thinking about, hey, what is that referring to in development? let's use a different color now.
02:29
So development.
02:31
Is it referring to the polarity of the earth? no, we're thinking about it in animal development.
02:37
So we know that there's this thing called an egg.
02:42
Okay, here's a little yolk inside that egg.
02:45
And we know that there is some genetic information in all of this.
02:51
So when we're looking at this, there can be an unequal amount of dna.
02:57
In or not dna concentration at different concentrations throughout this so that is what is considered polarity that's what this is referring to um when this process of polarity is happening um this is happening before the blast of four okay um is made so i'm going to write over here kind of a code so we're going to do before and then we're going to do after and do and do during.
03:37
So we're going to think about that specifically when it comes to what point before the blastomere is this process happening.
04:01
Okay? and we're going to use that because once we're having cytokinesis with everything, we want to make sure that we are taking that into effect because when it's going to make more cytoplasm is going to be before that.
04:23
Blastomere is created.
04:25
Sorry if that make you confused.
04:28
So basically we're looking about blastomeres.
04:30
After the blastomere is made, that's a certain point in development.
04:33
There's going to be before, after, and during.
04:36
And while that is being made, before it is being made, there is still going to be cytoplasmia.
04:41
So with this polarity, which is option a, we know that it's not that because that's happening before the blastomeres made.
04:49
Okay? so cytokinesis is still going, on and mitosis is also happening but we know that this is wrong okay let's do blue again sorry so b so here we have cleavage and this is a process that happens after fertilization okay so cleavage just think you're going to use a cleaver so we can think okay this is like it must be something dealing with that and we know that the zygote here is going to be undergoing repeated mitosis, right? and that's why it's called cleavage.
05:41
And so we're going to sit there and we're going to go, okay, when that is happening, that's when the dna of the cells is going to keep on multiplying, right? you've seen it where it goes like there's a little cell and it's like one, two, and then it spreads it to four and then it spreads, you know, a million, a million, it's impressive, right? that's what it's referring to.
06:02
When that's happening, there wouldn't be more cytoplasm, basically, because we know that it's multiplied.
06:11
So why would it need to stabilize itself with this like gooiness? anyway, we already know that b is the right answer.
06:17
But we're going to keep going because we have to.
06:21
And we're going to talk about the other options.
06:23
And maybe it could be multiple.
06:26
But really the point of this question is to learn something.
06:28
It's not just to get the answer right.
06:30
Okay, dokey.
06:31
So option c is gastrolation.
06:38
So when we're talking about gastrolation, we are going to be referring to the entire process of cell rearrangement.
06:50
And basically we're going to be looking at ingression, invagination.
06:57
Basically, think of it like your gastrointestinal system, and thus important, but there's obviously going to be some gooiness or cytoplasm involved.
07:09
We know that that is not right because it is happening before.
07:16
And basically when you're having, so basically, sorry for saying basically so many times.
07:21
The mesoderm here is going to be giving rise to your skeletal system, okay? and you're going to have all these differentiations.
07:29
You're going to have the endoderm, which is going to do the gas, i mean the digestive tract.
07:35
And we're going to have important parts.
07:39
This is going to happen after the blastomere is formed...