-
These contain molecules of DNA, the building blocks of life.
VOA: special.2010.02.02
-
So, that, for me, was kind of the first connection that what went, "Woah, wait a second, I want to be thinking about these molecules all the way down to the level of individual atoms."
接下来我遇到的一个问题,哇哦，等等，让我想想，是我在学习,有机化学的时候“
-
Then we're going to actually use MO theory to describe bonding within these molecules, and we'll start with homonuclear diatomic molecules.
然后我们要利用MO理论,来描述这些分子内的成键，我们要讨论同核双原子分子。
-
You know that these molecules are also linked in another way, by the phosphate bonds that connect the 3 and the 5 carbons of adjacent nucleotides.
这些分子还通过别的方式连接在一起,例如通过相邻核苷酸的3碳位和,5碳位之间的磷酸键相连
-
While these gas molecules or atoms through first approximation, are like hard spheres.
可以看做刚性小球,每一个分子会占据。
-
These are so-called homo-polar molecules.
这就是所谓的均匀极化的分子。
-
If God gathers up all those small molecules, that had composed my body, reassembles them in the right order and put these calci molecules next to that hydrogen molecules, so forth and so on, reassembles them in a right way.
如果上帝重组了所有构成我肉体的，微粒分子，将它们以正确的次序重组,把大量的钙生分子和,氢分子放在一起，组合起来，将它们以对的次序重组。
-
This is the strongest memory I have, and I remembered a) that I didn't learn them, and that was really bad because it kept coming up, but the other thing I remember is that I had no idea why they were important. I didn't really understand what any of these molecules were.
这就是我最深刻的记忆，我记得我并没有学好，这十分不好，因为之后它们总是不断出现,但另外的事情我记得,是我完全没有概念为什么。
-
So what happens when you put these molecules in water?
那么你把它们放入水中时会发生什么
-
We'll see why they have to separate that in a minute, but they do that these lipid bi-layers solve that problem for them and they're self-assembled structures from these molecules called phospholipids.
我们马上会讲到为什么要把它们隔离开,脂质双层膜解决了这个问题,而这些自主装结构,就是由磷脂分子组成的
-
There are 100 of these molecules, when a receptor gets activated a kinase activity gets activated, the kinase acts on the protein, the protein gets switched on, something new starts to happen inside the cell.
有一百个这样的分子,当受体被激活,激酶被激活后,激酶作用于蛋白,使蛋白活化,细胞中就会发生一些新变化
-
Because these molecules can span across the membrane from outside to inside, they're in just the right position to take messages that they receive from outside the cell and transmit them through the membrane into the cells internal apparatus, and that's what they do.
因为这些分子能穿过细胞膜,连通细胞内外,它们所在的位置非常适于接受信息,它们能将外界获得的信息,通过细胞膜传递给细胞器,这正是它们的功能
-
And what I'll mention to you just in terms of the fact that -- we're finally dealing with real molecules, which is -- or molecules that are made up of more than one atom, which is kind of exciting for me and maybe for some other of you that like to move into thinking about what some of the consequences of these molecules reacting might be.
而我将要告诉大家的是,我们终于开始与真正的分子打交道了，或者说由多于一个原子所组成的分子，这让我和你们中的某些人感到有些兴奋,因为我们更喜欢思考这些分子,经过反应之后可能出现的一些结果。
-
These molecules of DNA, very long molecules of DNA, are condensed and packaged within the nucleus of every cell in your body.
这些DNA分子是非常长的,它们通过折叠等方式压缩形成染色体后,被装配在你身体内的每一个细胞内
-
So, I think we have these molecular orbital energies down, so let's move on to talking about more complex molecules.
分子轨道能量就说到这里，让我们继续来讨论一下更复杂的分子。
-
These are molecules that exist naturally in cell membranes and are activated by certain enzymes and kinases generated by receptors.
这些分子存在于细胞膜表面,能被受体激活的某种酶或激酶所活化
-
This is a new concept, receptors don't have to be these molecules on cell surface, there can be receptors that exist in other places within the cell.
这是一个新概念,受体分子不一定只存在于细胞表面,它们也可以存在于细胞内其它地方
-
The balance of sodium movement relative to potassium movement changes because there's this resting movement of all these molecules anyway, but that balance changes dramatically when these ion - when these gated ion channels open.
钠钾各自运动始终保持动态的平衡,因为尽管在静息状态,所有这些离子也在运动,但是平衡的剧烈变化,只发生在这些门控离子通道打开的时侯
-
They have two fatty acid chains and so these are the oily like parts of the molecule, the molecules that behave like oil.
它们含有两条脂肪酸链,这是部分分子具有油脂的属性,使磷脂分子具有油脂的属性
-
So, for example, just talking about hydrogen cyanide or the cyanide anion, these are both molecules which are used in organic synthesis, so particularly the cyanide anion and salts of the cyanide anion.
那么，比如，就拿氰化氢,或者氰离子来说，它们都是用于有机合成的分子，特别是氰离子和氰离子的盐。
-
We're going to talk more about these kinds of molecules on the surface next week.
我们下一周,会再讨论这些表面分子的内容
-
These kinds of molecules which activate genes, they're activating the process of transcription.
这种分子能够激活基因,激活了转录过程
-
What you could do then, if you could deliver these red colored molecules here is you could stop specifically the expression of this particular gene in these particular cells.
接下来你能做的是,如果你能将这些红色的分子送到这里,就能够特异地阻止,特定细胞中特定基因的表达
-
These are fascinating molecules that turn out to be ubiquitous.
这类奇妙的分子是普遍存在的
-
One of the reasons why you would want to segregate things into certain regions is that molecules have to move in order to accomplish these things; molecules have to move from one place to another.
将细胞功能定位于某个固定区域的,另一个原因是,生物大分子需要移动,以完成某些功能,分子从一个地方移动到另一个地方
-
When a certain enzyme is activated inside cells, ATP gets converted into a molecule called cyclic AMP, and cyclic AMP is an example of one of these molecules called second messengers.
细胞内的某种酶被激活后,ATP就能转化为一种叫cAMP的分子,cAMP是一种第二信使分子的范例
-
The native structure is this double stranded structure here and if I heat it up slightly and I add some base, so under slightly basic conditions, these molecules will fall apart because you've created conditions where the hydrogen bonding is no longer favorable so they peel apart.
原始结构,在这里就是指DNA双链,如果我稍微加热,并且加入一些碱,在弱碱性的条件下,这些配对碱基会分开,这是因为在一定条件下,碱基对之间的氢键,不再稳定并且会断裂分开
-
These proteins have functions that are essential for life of the cell, they transport molecules back and forth across the membrane.
这些蛋白所起的功能,对于细胞生存至关重要,它们负责转运分子通过细胞膜进出细胞
-
And the reason we didn't do that is because we're actually going to spend much of the rest of the course relating these different properties to the properties of molecules in terms of bonding, and also in terms of chemical reactions.
我们至今没有这样做的原因是,实际上我们这门课程以后的大部分时间都将花在,如何将这些性质与分子的性质联系起来,在成键以及化学反应的方面。
-
Now, these are special channels in that they only allow certain molecules to pass through.
这种特殊的通道,只能允许特定的分子通过
应用推荐