1.Find the RF scaling with N for 2 dimensions in the limit of a good solvent. Hint: Start with
ΔG = ΔH – TΔS. Does ΔS change? What is the end-to-end vector distribution in 2 dimensions
(look in Lodge chapter for ideal chains equation 6.7.10)? In 1 dimension? What is the
probability of finding two monomers interacting? What is the dimension of a ‘volume’ in 2-
dimensions? Bonus: Find the scaling for an arbitrary dimension.
2.Use Image J (Free software) to calculate the persistence length of DNA adsorbed to mica
(taken with AFM). Hint: What is the contour length? What is the end-to-end vector? Look in
Lodge chapter for idea chains equations 6.4.11 and 6.5.3, one is complete the other is an
estimate. Estimate the persistence length with each one. Are the answers similar? Assume that
lp in 2 dimensions is the same as in 3 dimensions.
