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Forensic Science: Genetic Analysis

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Analysis of DNA samples to identify individuals by characteristics of their DNA, known as DNA profiling, is used in forensic science to establish the guilt or innocence of criminal suspects, to identify victims, to determine paternity, and to contribute to basic research. The polymerase chain reaction (PCR) is used to replicate certain regions of the DNA sample. The short tandem repeat (STR) analysis is used to compare the length of STR sequences at specific sites in the genome. In the restriction fragment length polymorphism (RFLP) analysis, a DNA sample is cut into small pieces using a restriction enzyme, which are them separated by size and made visible on a gel.

Population evolution, the generation-to-generation changes in a population’s frequency of alleles, can be used to estimate the frequency of a harmful allele, which can be useful in dealing with genetic diseases. Three examples of this evolution are genetic drift, gene flow, and natural selection. Genetic drift is a change in the gene pool of a small population due to chance. Gene flow is a genetic exchange with another population, which may add or remove alleles. In natural selection, the individuals with heritable traits suitable to the local environment generally leave more surviving, fertile offspring. …show more content…
Bacteria’s sole purpose is to replicate. Some are beneficial and even necessary to animal life, while others, called pathogens, are harmful and cause disease. Protozoans are protists that live primarily by ingesting food; they thrive in all types of aquatic environments. Algae are photosynthetic protists whose chloroplasts support food chains in fresh-water and marine

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