Most scientific works start with a main question. The strategy required to answer such question is well established by the scientific method. This involves the finding of evidences, a rigorous and critical evaluation of the results and the formulation of conclusions. However, this process usually opens new questions. Some of them cannot be avoided and must be addressed to reach the final goal. Some others are out of the scope of the research and they are left open for future investigations. This fact is specially marked in experimental sciences. Sometimes, the results of the experiments are unexpected and the investigations must focus on issues initially not predicted. This is what science is about: answering one question leads to another one.
A lot of new questions have emerged during the realization of this PhD thesis. Some of them were crucial and they had to be addressed. For instance, the measurement of the elastic response of the ssDNA in Chapter 5 was an unexpected experiment. Such experiment became essential to complete the data analysis. So the main question forced to answer secondary questions. Apart from that, new questions that have not been addressed have emerged. Following, there is a summary of the most relevant of them.