These arteries eventually branch into the arterioles, the smallest of the arteries.

这些脉最终会分支为小脉，即最小的脉。

A small alley is as small to the city as an arteriole 0.1 millimeters wide is to you.

一条小巷之于一来说，就像一条0.1毫米宽的脉对你来说一样渺小。

Well in response to low oxygen levels, or hypoxia, the pulmonary arterioles constrict, which raises the pulmonary blood pressure.

为应对低氧水平或缺氧，肺小脉会收缩，这就容易引起肺高血压。

Instead the glomerulus funnels blood into efferent arterioles which divide into capillaries a second time.

而是由肾小球将血液输进入出球小脉，后者分支复成毛细血管网。

If your blood pressure happens to increase, for example, the higher pressure causes the arterioles leading to your glomeruli to stretch.

例如，如果你的血压碰巧上升，高的压力会导致导致肾小球的小脉伸展。

Nitric oxide producer to dilate arterioles so that you feed more liquid to capillaries.

一氧化氮生成器，用于扩张小脉，从而向毛细血管输液体。

So with vasodilation of the arterioles, more heat gets lost which, therefore, helps to lower body temperature.

因此，随着脉血管舒张，热量会流失，有助于降低体温。

We previously learned that arterioles have a smaller diameter than arteries.

我们以前了解到，小脉的直径比脉小。

A small alley is as small to the city  as an arteriole 0.1 millimeters wide is to you.

一条小巷之于，就像一条0.1毫米宽的脉之于你。

Just like in the lungs, the aorta branches into arterioles which are smaller arteries and, finally, into capillaries which are the smallest.

就像在肺部一样，主脉分叉为小脉，最后变为毛细血管。

Vasodilation of the arterioles decreases resistance and increases blood flow.

小脉血管扩张减少了阻力，增加了血流量。

The cortical radiate arteries continue to divide eventually forming afferent arterioles that split into a tiny bundle of capillaries called the glomerulus.

小叶间脉继续分支，最后形成入球小脉；后者再分成若干小支形成一团微小的毛细血管球，即肾小球。

This process of glycation particularly affects the efferent arteriole and causes it to get stiff and more narrow - a process called hyaline arteriosclerosis.

这种糖基化过程尤其影响出球小脉，使其硬化、变窄——该过程叫玻璃样脉硬化。

Therefore, we see that the small arterioles are able to provide a significant amount of control over the flow of blood.

因此，我们看到，小脉能够提供对血液流的大量控制。

The smallest subdivisions of arteries, the arterioles, have thinner walls in which there are very little connective tissues but relatively more muscle.

脉的小分支（小脉）携血液至最小的血管（毛细血管）。

Blood flow to individual organs, or throughout the entire circulatory system, can be regulated by changing the diameter of the arterioles.

流向各个器官或整个循环系统的血液可以通过改变小脉的直径来调节。

So that blood goes from the pulmonary artery into a pulmonary arteriole, which is a little bit smaller and, finally, into a capillary which is the smallest.

血液从肺脉进入较细小的肺小脉，最后进入毛细血管。

On the other end of the capillary bed there's a venule, and the arteriole and venule are usually directly connected by a vessel called the metarteriole.

在毛细血管床的另一端，有小静脉；小脉和小静脉通常是由一种叫后微脉的血管直接连接的。

Of all of the blood vessels in the body, the most important ones to consider when we talk about resistance to blood flow are the arterioles.

在体内所有的血管中，当我们谈到血流阻力时，最重要的是脉。

In fact, the mesangium is continuous with the smooth muscles of the afferent and efferent arterioles, and fills in the space between the loops of blood vessels, hence the name.

事实上，系膜是由入球、出球小脉的平滑肌细胞延续而来，填满了毛细血管袢的空隙，因此得名Mes-angium。