鱼类和两栖类动物幼体主要的呼吸方式.进行呼吸的部位主要在鳃片（硬骨鱼为鳃丝）支持的鳃小片上，鳃小片由单层上皮细胞、支持细胞和毛细血管组成.水流通过鳃小片时，毛细血管中红血细胞携带的ＣＯ２能充分同水中的Ｏ２进行交换.鳃上的血液循环是鳃呼吸的保障.入鳃动脉将含ＣＯ２多的血液输入鳃间隔，在鳃间隔上分两支进入每个半鳃，每支发出若干细支进入鳃片，每细支的鳃小片上形成毛细血管网.气体交换后携带着多Ｏ２血，由逐步汇合成的出鳃动脉血管输出鳃，再运送至各组织器官.鳃的运动是鳃呼吸的必需条件，它使水沿着一定途径流动，鳃隔（软骨鱼）和鳃盖（硬骨鱼）的启开，犹如泵的作用，将水从口腔中抽出.口瓣膜关闭，防水倒流，使水始终保持从口进入经鳃裂流出的流动方向.GOOGLE英文翻译:Fish the main breathing patterns. To breathe the site mainly in the gills tablets (bony fish gill filaments) support the gills of a small chip, small piece of gill epithelial cells from the monolayer, composed of Sertoli cells and capillaries. Water through the gills of small films, capillaries in the red blood cells carry CO2 can be fully exchanged with water to O2. gill blood circulation on the gill respiratory protection. into the branchial artery to enter the blood with CO2 and more gill spacing, in the gills into the two sub-intervals of each one and a half gills, each issued a number of fine branches into the gill pieces, each small branch small piece of gill capillary network formed. After the gas exchange more O2 carrying blood from the gradually merge into the output of a gill gill arteries, and then transported to the various tissues and organs. gill movement is a necessary condition of the gill breathing, it makes the water flow along a certain way, gill septum (cartilaginous fish) and gill cover (bony fish) is being opened, as if pumping the role of the water from the mouth out. mouth off valves, water back, so always keep the water from the mouth into the flow through the gill slits of the flow direction. Related term: fish | invertebrates | Amphibia | fish | Lungfish | Animals | Dragonfly | animal tissue | breathe Organ |