When this fluid builds up, it makes gas exchange inside the alveoli much more difficult.

当这些体积聚起来后，就会使肺泡内的空气转换更加困难。

At the end of each branch is a tiny air sac called an alveolus.

在每个分支的末端都有一个叫做肺泡的小气囊。

Ultimately though, TB can avoid the mucus traps and make its way to the deep airways in alveoli where we have macrophages which eat up foreign cells, digest and destroy them.

然而最终，结核分枝杆菌可以避开被粘膜所困，然后到达深部呼吸道里的肺泡；在肺泡内有巨噬细胞可以吞噬掉异物并在细胞内部消化并且破坏异物。

Gas exchange in the lungs, so oxygen moving from the alveoli into the blood and carbon dioxide from the blood into the alveoli are both great examples of diffusion.

肺部行气体交换，因此氧气从肺泡入和二氧化碳从入肺泡都是扩的很好的例子。

Because that's because each sac contains a cluster of alveoli, these tiny cavities lined with super thin, wet membranes made of simple squamous epithelium tissue.

因为这是因为每个囊包含一簇肺泡，这些微小的空腔内衬着由简单鳞状上皮组织制成的超薄湿膜。

It then fills the alveoli, tiny air sacs that enable the exchange of oxygen and carbon dioxide between the lungs and blood.

然后填充肺泡，微小的空气囊能使氧气和二氧化碳在肺部和之间交换。

The alveoli are tiny air sacs that look like tiny clumps of grapes, that are wrapped up in a net of capillaries.

肺泡是微小的气囊，看起来像小丛葡萄，包裹于毛细管网中。

And if there's one thing your body hates, it's a bunch of exotic material spicing up your sensitive alveoli!

如果有你身体讨厌的东西来的话，就是一堆有毒的东西让你的肺泡激动起来了！

Free from particles, the inhaled air is now in the alveolus surrounded by mostly type I pneumocytes.

移出异物后，肺泡中的空气周围围绕的大多是I型肺泡细胞。

In the organs, the red blood cells line up alongside tissue cells and drop off oxygen, as well as pick up carbon dioxide basically the reverse of what happens with the alveolus in the lung.

在器官中，红细胞与组织细胞排列在一起，并释放氧气，同时吸收二氧化碳；基本上与在肺泡处的情况相反。

Initially, doctors had no way to alter the stretchability or squeeziness of their patients' air sacs.

最初，医没有办法改变病人肺泡的拉伸性或挤压力度。

Emphysema is when the tiny structures in your lungs called alveoli, break down.

肺气肿是指肺中被称为肺泡的微小结构破裂。

So it's your alveoli where diffusion meets bulk flow. Because while you're picking up oxygen and dispensing with CO2 one molecule at a time, you're doing it in enormous quantities at any given second.

所以你的肺泡是扩与容积运动相遇的地方。因为当你吸收氧气并一次释放一个分子的二氧化碳时，你在任何给定的时刻都在做大量的事情。

Bacterial growth and death of alveolar macrophages produce powerful chemotactic factors that cause a large influx of polymorphonuclear leukocytes and monocytes from the peripheral blood.

军团菌的增长及肺泡巨噬细胞的死亡产了强大的趋化因子，造成大量多形核白细胞和单核细胞从外周涌入。

That problem happens deep in the lungs, in tiny air sacs called alveoli, which exchange carbon dioxide for oxygen.

这个问题出现在肺部深处，叫做肺泡的微小气囊中，肺泡是将二氧化碳转化为氧气的部位。

Most are regular pneumocytes called type I pneumocytes, but some, called type II pneumocytes, have the ability to secrete a substance called surfactant, which helps decrease the surface tension within the alveoli and keeps them open.

大部分为I型肺泡细胞，还有一些为II型肺泡细胞可以分泌一种表面活性剂，这有助于降低肺泡内的表面张力，并保持它们的开放。

Preemies' lungs haven't yet developed enough of these surfactants, so the small alveoli squeeze too much and collapse, while the larger ones keep blowing up and get distended.

早产儿的肺还没有长出足够的表面活性剂，所以小的肺泡因挤压出太多的气体而塌陷，而大的肺泡则不断膨胀。

In atypical or interstitial pneumonia, the infection is mainly just outside the alveoli in the interstitium.

在非典型肺炎和间质性肺炎中，感染主要发在间质的肺泡外。

Now, in the lungs, if we zoom in on a tiny alveolus—where gas exchange happens— if there's some sort of infection or other cause of inflammation, immune cells like neutrophils arrive on the scene.

在肺中，如果我们放大来看极其微小的肺泡，即气体交换的场所，如果受到某种感染或其他原因导致肺泡发炎症，免疫细胞（如中性粒细胞）便会抵达“战场”。

But in healthy people, alveoli stay properly inflated because they're full of chemicals called pulmonary surfactants that make the small alveoli more stretchy and less squeezy, balancing the pressure between air sacs.

但在健康的人体内，肺泡会适当的保持充气状态，因为肺泡中充满了一种叫做肺表面活性剂的化学物质，这种物质能使小肺泡更有弹性，挤压力度更小，从而平衡气囊之间的压力。