在研究“细胞的大小与物质扩散的关系”(七年级上·北师版)的活动中,由于本校实验条件的限制,在取材时,我们因陋就简,用均质的石膏块代替酚酞—琼脂块,取得了很好的实验效果,在此写出来以期抛砖引玉,具体做法如下:一、取材选取均质的石膏块,切成边长为1cm、2cm、3cm 石膏立方体,以示大小不同的细胞。用红墨水(黑、蓝也可) In the study of the relationship between the size of cells and the diffusion of substances (September 7th, Beijing Normal University Edition), due to the limitations of the experimental conditions of our school, we used simple homogeneous plaster blocks instead of phenolphthalein-agar blocks at the time of sampling. , Have achieved good experimental results, written here to start with jade, the specific approach is as follows: First, the material selection of homogeneous plaster blocks, cut into side length 1cm, 2cm, 3cm plaster cubes, to show different sizes of cells. Red ink (black and blue is also available)