Final answer:
Under high salt conditions and with sequences containing alternating purines and pyrimidines, B DNA is more likely to convert to Z DNA. Methylation of certain bases can also promote the formation of Z DNA, particularly in low salt conditions. DNA methylation's effect on gene expression and the DNA denaturation-reannealing process are important for understanding DNA's functionality.
Step-by-step explanation:
Under certain conditions, B DNA can be converted to Z DNA. For example, under high salt conditions, sequences that contain alternating purines and pyrimidines are more likely to convert from B DNA to Z DNA. Also, under low salt conditions, the methylation of certain bases will promote Z DNA formation. DNA methylation occurs within specific regions called CpG islands, which can influence gene expression. Changes in DNA denaturation and reannealing, due to modifications like heating, play a crucial role in the overall structure and function of DNA, often serving as a basis for a variety of biotechnological techniques.