Topic one Flashcards
Give two reasons why base pairing is important.
The strands complementary to each other. Adenine and thymine AT2 hydrogen bonds and guanine GC3 hydrogen bonds. Complementary base pair ensures DNA maintains a regular structure and does not unfold or denature, causing it to lose biological structure. The base pairing allows transcription and DNA replication to occur allows for large amount of information to be stored.
Describe the DNA structure found in prokaryotes, where it is found and how the spatial arrangement is organized.
Prokaryotic cells have singular, circular chromosome located in cytoplasm called nucleoid, they don’t have histones but have proteins that assist in the spatial organisation in the nucleoid.
Explain the DNA replication steps.
Helicase breaks the weak hydrogen bonds, free nucleotides bond to the complementary base pairs on the template strands. Hydrogen bonds are then, and DNA polymerase attaches sugar phosphate groups allowing a backbone to form for the newly synthesised polynucleotide strands.
Explain the process of modification of the mRNA.
mRNA synthesised is Pre-mRNA due to its prematurity, as it is modified before translation. Pre-mRNA is modified by splicing spliceosomes remove introns to make only exons in the mRNA.
Describe the ethical, economical and cultural issues with collection of genetic information
Genetic information collection problems
Potential for discrimination: There is a risk that insurance and prospective employers may discriminate on the basis of genetic health.
Ownership: The genetic information obtained from an individual should be the legal property of the individual.
Privacy and confidentiality: The results of the genetic test have the potential to be shared with other parties without the permission of the owner.
Emotional impact on the individual: The results of the genetic screening have the potential to be emotionally distressing and genetics counselling is required. Some genetic illnesses have no known cure or effective treatment.
Impacts on the family members. Genetic testing of an individual can also reveal genetic information about a person’s family. The potential emotional impact on family members be considered.
Impact on children: Genetic testing of an individual may be carried out during infancy at the request of the parents. The child did not give informed consent and may not wish to know their potential risk factors.
Social implications: The results of genetic testing have the potential to make an individual feel socially deprived, psychologically traumatised, or stigmatised by attitudes towards genetic differences.
Impact on reproductive choices: Knowledge that a prospective parent has a genetic disease may impact their decision to have children. This decision is normally influenced by individual, family, religious and cultural belief.
Limitations: Genetic testing can provide information about the nature of potential risk factors for genetic disease but rarely predicts the severity of the condition or age at which symptoms will onset. Environment is a factor in the development of genetic disease.
Inaccuracies: There is always a possibility that genetic information is inaccurate or is misinterpreted. The impact of a false positive or negative result from genetic testing could be devasting.
Reliability: The results of genetic testing may prove to be an unreliable indicator of developing a genetic disease. Longitudinal studies are required to asses the reliability of genetic testing in accurate diagnosis of genetic disease.
