21. This is also referred to as the movement of a substance down a concentration gradient . 22. In dialysis and pervaporation the chemical potential along a concentration gradient is the driving force. 23. Gases may diffuse in either direction depending on the concentration gradient between the two layers. 24. In the case of dialysis, the driving concentration gradient in the membrane is reduced. 25. Facilitated diffusion may be achieved as a consequence of charge gradients in addition to concentration gradients . 26. He presented the sequences nonlinear concentration gradient , prompting a whimsical article in the popular press. 27. A morphogen spreads from a localized source and forms a concentration gradient across a developing tissue. 28. This is due to urea entering the cell down its concentration gradient , followed by water. 29. Alarmingly, concentration gradient was a redlink, so I've redirected it to diffusion. 30. Ions diffuse across their concentration gradient from the fluids of the tuna to the external seawater.
