Question

DNA fingerprints used as evidence in a murder trial look something like supermarket bar codes. The pattern of bars in a DNA fingerprint shows ________?

1) the order of bases in a particular gene
2) the presence of dominant or recessive alleles for particular traits
3) the exact location of a specific gene in a genomic library
4) the presence of various-sized fragments of DNA
5) the order of genes along particular chromosomes

Answer 1

A DNA fingerprint shows the presence of various-sized fragments of DNA, separated by gel electrophoresis to form a unique pattern for each individual.

Step-by-step explanation:

The pattern of bars in a DNA fingerprint shows the presence of various-sized fragments of DNA. DNA fingerprinting involves extracting DNA from samples, such as blood or saliva, and then using restriction enzymes to cut the DNA into fragments.

These fragments are then separated by size through a process called gel electrophoresis, resulting in a unique banding pattern for each individual, which can be visualized and compared. This technique is widely used in forensic science for crime scene investigation, as well as in paternity testing and genetic research.