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In the context of PCR technology, "elongation" and "extension" are indeed often used interchangeably to describe the same process, where the DNA polymerase synthesizes a new strand complementary to the template strand. During this phase, the polymerase adds nucleotides to the 3' end of the primer, thus extending the DNA strand. However, the term "elongation" is sometimes more specifically associated with the kinetics of the process, such as in measuring the elongation efficiency in various conditions [1][5][6]. On the other hand, "extension" is more commonly used in standard PCR protocols and guidelines [2][3][4]. Thus, while both terms refer to the same phase in PCR, "elongation" might be used in a more technical context to discuss the efficiency and dynamics of the polymerase action.

Reference

[1] Horton, R., Cai, Z., Ho, S., & Pease, L. (2013). Gene splicing by overlap extension: tailor-made genes using the polymerase chain reaction.. BioTechniques, 8 5, 528-35 .

[2] Hussain, H., & Chong, N. F. M. (2016). Combined Overlap Extension PCR Method for Improved Site Directed Mutagenesis. BioMed Research International, 2016.

[3] Montgomery, J., & Wittwer, C. (2014). Influence of PCR reagents on DNA polymerase extension rates measured on real-time PCR instruments.. Clinical chemistry, 60 2, 334-40 .

[4] Huang, M., Arnheim, N., & Goodman, M. F. (1992). Extension of base mispairs by Taq DNA polymerase: implications for single nucleotide discrimination in PCR.. Nucleic acids research, 20 17, 4567-73 .

[5] Yamagami, T., Ishino, S., Kawarabayasi, Y., & Ishino, Y. (2014). Mutant Taq DNA polymerases with improved elongation ability as a useful reagent for genetic engineering. Frontiers in Microbiology, 5.

[6] Cheng, B., & Price, D. (2007). Properties of RNA Polymerase II Elongation Complexes Before and After the P-TEFb-mediated Transition into Productive Elongation*. Journal of Biological Chemistry, 282, 21901 - 21912.

In the context of PCR , the terms "elongation" and "extension" are often used interchangeably, though they can have slightly different nuances. Both refer to the phase where DNA polymerase synthesizes a new DNA strand by adding nucleotides to the 3' end of the primer. The term "extension" is more commonly used in PCR protocols to describe this specific step, where the DNA strand is being extended. On the other hand, "elongation" emphasizes the process of the DNA strand progressively lengthening as nucleotides are added sequentially. Despite these subtle differences, both terms describe the same critical process in PCR where DNA is synthesized by the polymerase enzyme.

no different between two term it same in pcr