Alevel生物哺乳动物知识点梳理!哺乳动物的运输(下)
2023-09-22 14:44:18 浏览量:0次
正如大家所知,Alevel生物课程的难度相对于国内生物课程的难度要稍微高一些。它不仅仅体现在实验操作性强上,更在基础知识的深度和广度上。在学习的过程中,很多同学反映不知道怎么记忆那些知识点,也不知道如何将知识点运用到实践中,在写论文时更是发愁。针对这些困难,小编为大家梳理了中英对照版本的alevel生物知识点梳理,共分为三篇,同学们可检索关键词获得更多资料,那么现在就一起来看看吧!
This diagram shows the formation of tissue fluid 这张图显示了组织液的形成:
Veins 静脉
The capillaries then join to form larger venules which themselves then join to form veins.
然后毛细血管连接形成更大的静脉,静脉本身又连接形成静脉。
Since at this stage, the pressure of the blood is low, blood needs to be 'encouraged' to flow back to the heart. To prevent any backflow of the blood (particularly important if blood is flowing against gravity) there are valves in the veins. Also the veins pass through or very close to muscles. When the muscles are active in contracting and relaxing, the squeezing on the veins moves blood along but due to the valves, only ever towards the heart.
由于在这个阶段,血液的压力很低,所以需要"鼓励 "血液流回心脏。为了防止血液倒流(如果血液逆向流动尤其重要),静脉中设有阀门。此外,静脉穿过或非常接近肌肉。当肌肉活跃地收缩和放松时,对静脉的挤压会使血液流动,但由于阀门的存在,血液只能流向心脏。
As the pressure is so much lower in the veins than in the arteries, there is little need for the elastic fibres and smooth muscle in the walls.
由于静脉中的压力比动脉中的低得多,所以几乎不需要血管壁上的弹性纤维和平滑肌。
以上就是小编为大家整理的有关Alevel生物的知识点梳理,希望对大家有所帮助,祝学业有成金榜题名!如有更多有关Alevel课程辅导的需要,欢迎来联系在线客服老师,会获得更多专业的指导哦~