module seven forensic science

Module Seven: Text Questions
Review Questions
1. What is DNA? Where is it found? DNA is deoxyribose nucleic acid. It contains genetic information. Found pretty much anywhere; including saliva, hair strand, etc.
2. What is mitochondrial DNA? DNA located in the mitochondria
3. What is CODIS? How does it work? CODIS is the combined DNA identification system. It has a database full of DNA samples from criminals and others who voluntarily gave their DNA.
4. What are complimentary base patterns? Why are they important? Adenine, thymine, cytosine, and guanine. They are important to the structure of the DNA
5. What is RFLP? What are some of the limitations of this technique? RFLP is a method used by molecular biologists in order to follow a sequence of DNA as it is passed on to other cells.
Critical Thinking Questions
1. Why do you think DNA has had such an impact on forensic science? It has allowed us to advance as a society, making it possible to serve justice.
2. What do you think would be some of the challenges in collecting DNA evidence? How would you overcome these challenges? Sometimes DNA might get contaminated; for example, the person gathering the evidence accidentally spits while talking and gets saliva on a swab used to gather someone else’s DNA this may alter the evidence and in the end, maybe even cause for a mistrial to occur.
3. Compare and contrast nuclear DNA with mitochondrial DNA. Which one would you want to use in a criminal investigation if you had the choice? Nuclear DNA because it is more complex where mitochondrial DNA has less variability. Mitochondrial DNA is passed directly from mother to offspring in humans and nuclear DNA is mixed and matched, so is different.
4. Which of the DNA typing techniques do you think you would choose if you had to analyze a DNA sample? Why? I would use PCR because it is used by many scientists and is also cheap. This process basically replicates DNA strand so they can be used in other tests as well and it only takes a few hours which is beneficial in criminal justice because of the constant pressure of solving cases despite the fact that some evidence takes a long time to gather or treat.
5. What challenges do you think giving expert testimony about DNA would have? How would you try to overcome these challenges? You would have to be prepared to explain the process of finding the DNA and the comparison to the guilty person. If there are around 10 markers that are alike, then the possibility of having the wrong person would be one in several billion, so you have a better chance than a DNA profile matching only 2 markers. This is something you would have to explain and prove to the jury. Being well informed and knowing what you’re talking about would make you seem more confident because you’re not doubting yourself, plus credible work such as awards you’ve received in the past while researching this subject will increase your image of knowing what you’re talking about.