Fig. 3.

Lines representing protein under extensional flow, with two sets of points, leading and lagging. The line is unevenly stretched, with the distance between the leading set of points accelerating faster than the distance between the lagging set of points. The molecule is moving in the direction of flow. This is the type of extensional strain found on the left side of Fig. 2 below between A and B objects, as well as between B and C.