Figure 2
From: 'Single molecule': theory and experiments, an introduction
The Worm-Like-Chain model. (A) A polymer is viewed as a chain of colloids; Lp, persistence length, Lc, contour lengths, Le, end-to-end distance. Different polymers of the same contour length can be rigid (B), semi-flexible (C), or flexible (D); it is the ratio of Lc over Lp that determines the flexibility.