Liebman P A, Entine G
Science. 1974 Aug 2;185(4149):457-9. doi: 10.1126/science.185.4149.457.
Visual pigment molecules are found to move transversely, but not longitudinally, in both rod and cone outer segments of mud puppy and frog. This is consistent with the idea that they are immersed in a two-dimensional fluid disk membrane. The diffusion coefficient for the motion is about 5 x 10(-9) square centimeters per second at 20 degrees C, corresponding to a root-mean-square molecular displacement of 0.3 micrometer in 1 second.
在泥螈和青蛙的视杆和视锥细胞外段中，发现视觉色素分子进行横向移动，但不进行纵向移动。这与它们浸没在二维流体盘状膜中的观点一致。在20摄氏度时，该运动的扩散系数约为5×10⁻⁹平方厘米每秒，这对应于分子在1秒内的均方根位移为0.3微米。
