英语流利说 Level5 Unit3 Part2 The Cir
The Circulatory System 1
循环系统
A flow chart, like this one, shows how a process begins and ends, and the steps in between.
像这样的流程图显示了一个过程是如何开始和结束的，以及中间的步骤。
The process can be of almost any kind, from manufacturing a tire to creating an advertisement.
这个过程几乎可以是任何一种，从制造轮胎到制作广告。
Therefore, learning how to describe and explain a process in English is important.
因此，学习如何用英语描述和解释一个过程是很重要的。
It's important for teachers, engineers, and people who provide customer support.
这对教师、工程师和客户支持人员都很重要。
One process that we are all familiar with is our body's circulatory system.
我们都熟悉的一个过程是我们身体的循环系统。
This system provides oxygen throughout the body and eliminates carbon dioxide, which is a waste product.
这个系统为全身提供氧气，排除二氧化碳，二氧化碳是一种废物。
If something goes wrong with this system, we need to repair it quickly, or we die.
如果这个系统出了问题，我们需要尽快修复它，否则我们就会死。
So it's important to understand it and keep it functioning properly.
所以理解它并让它正常工作是很重要的。
What does the circulatory system do?It provides oxygen to the body and eliminates carbon dioxide.
循环系统是做什么的?它为身体提供氧气，消除二氧化碳。
It provides oxygen to the body and eliminates carbon dioxide.
它为身体提供氧气，消除二氧化碳。
It’s important to keep it functioning properly, or we will die.
循环系统是做什么的?它为身体提供氧气，消除二氧化碳。
First, the most important requirement for the system to work is a supply of air.
首先，系统工作的最重要的要求是空气的供应。
Without fresh air with sufficient oxygen, the process won't keep us healthy and alive.
如果没有新鲜的空气和足够的氧气，这个过程就不能保持我们的健康和生命。
So the process begins by breathing in air, which happens when the lungs expand and draw in air.
所以这个过程从吸入空气开始，当肺部扩张吸入空气时就会发生。
Once inside the lungs, oxygen in the air is exchanged for carbon dioxide in the blood.
一旦进入肺部，空气中的氧气就会与血液中的二氧化碳交换。
This exchange happens when blood cells release carbon dioxide and absorb oxygen.
这种交换发生在血细胞释放二氧化碳和吸收氧气的时候。
This blood is now oxygenated blood, which means it carries oxygen.
这种血液现在是含氧血，这意味着它携带氧气。
What kind of air is require to keep us healthy and alive? fresh air with sufficient oxygen
我们需要什么样的空气来保持健康和活力?新鲜空气和充足的氧气
To summarize,the process begins by inhaling air and oxygenating the blood.
总而言之，这个过程从吸入空气和给血液充氧开始。
The oxygenated blood in the lungs then flows back to the heart.
肺里含氧的血液然后流回心脏。
The C02 which came from the blood is exhaled, and the next cycle begins.
来自血液的二氧化碳被呼出，然后下一个循环开始。
Where does the oxygenated blood go?back to the heart
含氧血液流向哪里?回到心脏
Note that the blood in the lungs flows in a loop from the heart.
注意肺部的血液从心脏循环流动。
The blood which enters the loop from the heart carries carbon dioxide.
从心脏进入血液循环的血液携带着二氧化碳。
Once the carbon dioxide is exchanged for oxygen, the blood continues through the loop and exits into the heart.
一旦二氧化碳被转化为氧气，血液就会继续循环并进入心脏。
The oxygenated blood is then pumped to the rest of the body.
含氧的血液被泵到身体的其他部位。
What happens to the oxygenated blood after flows to the heart ? it's pumped to the rest of the body
流向心脏的含氧血液会发生什么变化?它被泵到身体的其他部位
To stay healthy and alive, we need fresh air with sufficient oxygen.
为了保持健康和活着，我们需要新鲜的空气和足够的氧气。
This happens when the lungs contract.
这发生在肺收缩的时候。
The system won't work without a supply of air
没有空气供应，这个系统就不能工作
The Circulatory System 2
As you can see, everything depends on the flow of blood to and from the heart.
正如你所看到的，一切都取决于血液进出心脏的流量。
So how does the heart do this?
心脏是怎么做到的呢?
First, the heart, which is a muscle, has 4 chambers.
首先，心脏是一块肌肉，它有4个心室。
From one chamber, blood is pumped to the lungs.
血液从一个腔室被泵到肺里。
This is the blood that carries carbon dioxide.
这是携带二氧化碳的血液。
When the oxygenated blood from the lungs comes back to the heart, it enters another chamber.
当肺中的含氧血液回到心脏，它就进入另一个腔室。
This chamber is called the left atrium.
这个腔叫做左心房。
What does the blood pump to the lungs carry? it carries CO2
输送到肺部的血液携带着什么?它携带二氧化碳
From the left atrium, the oxygenated blood is pumped into another chamber, the left ventricle.
从左心房，含氧血液被泵入另一个腔室，左心室。
The left ventricle then pumps the blood into the aorta, which is the largest artery in the body.
然后左心室将血液泵入主动脉，这是人体最大的动脉。
From the aorta, the oxygenated blood passes through a network of smaller arteries throughout the entire body, including the brain.
从主动脉开始，含氧血液通过整个身体的小动脉网络，包括大脑。
Blood returns to the heart through a system of veins and enters the upper right chamber, the right atrium.
血液通过静脉系统回到心脏，进入右心房。
what is the largest artery in the body？the aorta
人体内最大的动脉是什么?主动脉
Now that we understand a little about the circulatory system we can ask what it needs to operate.
现在我们对循环系统有了一些了解，我们可以问它需要什么来运作。
Of course it can't operate without energy.
当然，它不能没有能源。
This energy is supplied by another system, the digestive system, which gets energy from food.
这种能量由另一个系统提供，即消化系统，它从食物中获取能量。
And of course these systems need to be supported and controlled.
当然，这些系统需要得到支持和控制。
Our skeletal system provides support, and our muscular system provides control and movement.
我们的骨骼系统提供支持，我们的肌肉系统提供控制和运动。
Without support and movement, we couldn't get the food that we need for energy.
没有支持和运动，我们就不能得到我们需要的能量的食物。
Only plants can do this because they have a completely different system, which gets energy directly from the sun.
只有植物能做到这一点，因为它们有一个完全不同的系统，直接从太阳获取能量。
what supplies energy to the circulatory system？the digestive system
什么为循环系统提供能量?消化系统
What life forms get energy directly from the sun? plants
什么生命形式直接从太阳获得能量?植物
To summarize, the human body is like a huge, complex factory.
总而言之，人体就像一个巨大而复杂的工厂。
The language we use to describe how it functions is the same language we use to describe almost any industrial process.
我们用来描述它如何运作的语言和我们用来描述几乎任何工业过程的语言是一样的。
The vocabulary is different, but the processes, flows and logical relationships are almost identical.
词汇表是不同的，但是流程、流程和逻辑关系几乎是相同的。
Think of some familiar process in your life or job and see if you can describe and explain it in English.
想想在你的生活或工作中一些熟悉的过程，看看你是否能用英语描述和解释它。
Plants get energy directly from the sun by using photosynthesis.
我们需要什么样的空气来保持健康和活力?新鲜空气和充足的氧气
