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心血管是由心脏、动脉、静脉和毛细血管等组成的一个密闭系统。其中心脏是动力器官,它象一台泵一样日日夜夜,永不停息地推动血液在血管里沿着一定方向流动,运送氧气和多种营养物质,通过毛细血管输送给人体各器官内的每个细胞。同时,静脉血将组织细胞内所产生的二氧化碳和代谢废物通过各排泄器官排出体外,再返回心脏。就这样,血液在心脏推动下,周而复始地流动,维护着人的生命。心脏位于胸腔内,居隔肌的上方,两肺之间,稍偏左下方。心脏的形状象个桃子,尖朝下,底朝上,每个人的心脏大小跟自己的拳头差不多,与大血管相连。正常成
Cardiovascular is a closed system composed of the heart, arteries, veins and capillaries. The heart is the power organ, which, like a pump, like day and night, non-stop to promote blood flow in the blood vessels in a certain direction, carrying oxygen and a variety of nutrients through the capillaries to various organs of the human body Each cell. At the same time, venous blood will be generated within the tissue cells of carbon dioxide and metabolic waste excreted through the excretion of organs, and then returned to the heart. In this way, under the impetus of the heart, the blood flows in a continuous manner and maintains human life. The heart is located in the chest, above the dorsal muscle, between the two lungs, slightly off left below. Heart shaped like a peach, pointed down, bottom up, each heart size with their fist almost, connected with the large blood vessels. Normal into