点击这里观看更多视频: https://alugha.com/FuseSchool 在此视频的第一部分中，我们研究了气体运动的扩散和水运动的渗透。它们很容易从高浓度变为低浓度。这是有意义的，那么主动运输是为了什么? 主动运输是在浓度梯度下，将分子从低浓度转移到高浓度，这与扩散和渗透相反。因为这不是自然的方向，所以需要能量起作用。 主动运输由细胞膜内的蛋白质为载体，它们有一个特定的结合位点，可以准确地运输分子。该物质与低浓度一侧的蛋白质载体结合，利用呼吸的能量，蛋白质载体在细胞膜的另一边释放出浓度已经很高的物质。 我们的老师和动画师精诚合作，为化学、生物、物理、数学和ICT这些学科制作出简单易懂且充满趣味的视频。 加入我们的平台www.fuseschool.org 这些视频可用于翻转课堂或用作复习辅助。 Twitter: https://twitter.com/fuseSchool 本教育视频资源是开放且免费的，在知识共享协议下: 署名-非商业性CC by nc(查看许可契约): http://creativecommons.org/licenses/by-nc/4.0/ ). 你可以下载这段视频或在非盈利组织和教育机构使用。如果想修改视频，请联系我们: info@fuseschool.org
Algebraic fractions are simply fractions with algebraic expressions either on the top, bottom or both. We treat them in the same way as we would numerical fractions. In this video we look at how to simplify algebraic fractions, and how to add and subtract them. VISIT us at www.fuseschool.org, wh
CREDITS Animation & Design: Peter van de Heuvel Narration: Lucy Billings Script: Lucy Billings The word polygon comes from Greek. Poly means “many” and Gon means “angles”. Polygon = many angles. Polygons are 2-dimensional shapes, that are made of straight lines, with all the sides joined up. VISIT
In algebra we have lots of different names for different things: expressions, equations, formulae and identities are all slightly different versions of similar things. Then within these, we have variables, constants, coefficients and exponents to describe the different parts. We also need to know wh
