4 The Circulatory System

THE CIRCULATORY SYSTEM

循环系统

INTRODUCTION Your body is made up of millions of tiny living things called cells. Each of these cells needs oxygen and nutrients from food to keep you alive! Blood delivers oxygen and nutrients to your cells. But if it weren't for ME, your blood wouldn't go anywhere! I'M YOUR HEART!

你的身体是由数百万个被称为细胞的微小生物组成的。 这些细胞都需要食物中的氧气和营养来维持你的生命！血液为细胞输送氧气和营养。 但如果不是我，你的血不会流到任何地方！我是你的心！

I pump blood into a network of tubes called blood vessels. Together, the heart, blood vessels, and blood make up the circulatory system. HOP Plop The circulatory system carries blood to every part of your body, from your head to your toes! Let's take a closer look...

我将血液泵入一个叫做血管的管道网络。 心脏、血管和血液共同构成了循环系统。 循环系统将血液输送到身体的每一个部位，从头到脚趾！让我们仔细看看……

WHAT IS BLOOD? Blood is like a river of life flowing through your body. MMM! It supplies cells with oxygen and nutrients... ...and carries away wastes that cells produce. THANK YOU! My pleasure!

什么是血？血液就像生命的河流流经你的身体。 嗯!它为细胞提供氧气和营养。 ．．．并带走细胞产生的废物。 谢谢你！这是我的荣幸!

More than half of your blood is made of a watery, pale-yellow liquid called plasma. Blood also contains three different types of blood cells: RED BLOOD CELLS PLATELETS WHITE BLOOD CELLS Plasma carries these blood cells through blood vessels.

你一半以上的血液是由一种淡黄色的水状液体组成的，这种液体叫做血浆。 血液中还含有三种不同类型的血细胞：红细胞、血小板、白细胞、血浆通过血管携带这些血细胞。

RED BLOOD CELLS Each type of blood cell has a different job. Yet, each job is just as important as the other! Red blood cells transport oxygen throughout your body. Red blood cells are so small you could fit millions of them in this panel! In addition to being small, red blood cells are also pliable. They easily compress and stretch to fit through even the narrowest blood vessel.

每种类型的血细胞都有不同的功能。 然而，每一项工作都是一样重要的！红细胞将氧气输送到全身。 红细胞是如此之小，你可以在这个面板上装下数百万个红细胞！除了体积小之外，红细胞也很柔韧。 它们很容易压缩和拉伸，甚至可以穿过最狭窄的血管。