Final answer:
'Per DNA fragment' refers to the number of DNA fragments present in an experimental sample or a collection of DNA sequences. It is a term often used in DNA analysis techniques such as DNA sequencing and gel electrophoresis.
Step-by-step explanation:
'Per DNA fragment' refers to the number of DNA fragments present in an experimental sample or a collection of DNA sequences. In DNA analysis, researchers often use techniques like cutting DNA into fragments, sequencing them, or running them on a gel to study different aspects of DNA. For example, DNA fragments can be spotted on a glass slide to analyze an organism's genomic library or expressed genes. Additionally, DNA fragments from different samples can be run on a gel to determine their sizes and compare them.