1. Gaussian Chain
Entropy only.
Infinite extensibility.
2. Freely Jointed Chain.
Entropy. Finite extensibility.
Rigid rods. 
3. Wormlike Chain.
Entropy. Finite extensibility.
Bending elasticity.
Smooth curve like cooked spaghetti.

2. Persistence length 
 = 50nm
 = 6mm = bigger than a cell
 = 17m

6. Mechanism of DNA virus assembly and DNA packaging
Rao and Feiss – Annu Rev Virol (2015) 2(1): 351–378
Costs of DNA packaging:
DNA bending + Electrostatic repulsion of charged DNA + Entropic cost of confinement

7. Measuring the force generated by T4 DNA packaging motors
Fuller et al PNAS (2007) 104:
Tension in the DNA increases as packaging proceeds. Eventually the tether breaks. Speed of motpor decreases as tension increases.

8. Differential Scanning Calorimetry of Bacteriophage .
Exothermic peaks associated with Capsid denaturation and DNA melting.
Endothermic peak due to DNA ejection. Shows that there was significant stored energy in the packaged DNA
Bauer et al
J Virol (2015) 89:

12. Kunze and Netz (2000)

13. Brower-Toland et al 2002

14. Mihardja et al (2006)

17. Kulic and Schiessel 2004

18. Tomschik et al 2005