Final answer:
STR stands for Short Tandem Repeat, which is a DNA sequence used in DNA profiling for forensics and paternity testing, due to its high variability among individuals.
Step-by-step explanation:
The abbreviation STR stands for Short Tandem Repeat. STRs are repetitive sequences of DNA that are 2-6 base pairs in length. These sequences are found at specific locations on a chromosome, and the number of repetitions is highly variable among individuals.
This makes STRs particularly useful for DNA profiling in forensic science, as well as in genetic testing and paternity testing. In forensic cases, comparing the STR patterns between a suspect's DNA and DNA found at a crime scene can either implicate or exonerate the individual. Similarly, STR analysis can confirm biological relationships in paternity cases.