Analyzing the Eukaryotic Chromosome

Structural Elements of a Functional Eukaryotic Chromosome
The three essential structural elements of a functional eukaryotic chromosome are centromere, telomeres, and origins of replication. Centromere serves as the attachment point for the spindle fibers. A centromere is a region of DNA responsible for the movement of the replicated chromosomes into the two daughter cells during meiosis and mitosis. Joining the sister chromatids is one of the major functions of the centromere. The two copies of the replicated chromosome are referred to as sister chromatids, and they stay joined together until they are physically pulled into the two future daughter cells, which ensures that each daughter cell will receive exactly one copy of each chromosome. The second major function of the centromere is to attach the microtubules in the mitotic spindle. The centromere will direct the formation of the kinetochore. The kinetochore is a special protein structure that attaches to the microtubules in the mitotic spindle (Hennig, 2013). Telomeres are the natural ends of the linear eukaryotic chromosomes and they stabilize the ends of the chromosome. Telomeres are the caps at the end of each DNA strands that protect the chromosome from being damaged. If the DNA strands are damaged they will not be able to perform their job. Origin of replication is the sequence of DNA where replication of a chromosome is initiated. For small DNA's a single origin is enough, but for larger DNAs, there is need to have many origins and replication would be initiated in all of them. If replication was limited to a single origin, it would take too long to replicate the DNA mass.
Research has shown that telomeres shorten as an individual get older, which causes aging of the individual's cells. Numerous studies have been carried out that are aimed at learning more about telomeres, and there is new evidence being discovered regarding the role that telomeres play in the aging process. Telomeres are not only associated with aging, but also cancer and the risk of death. There is a direct correlation between chronic disease and telomeres. In terms of cancer, as cells begin to become cancerous they tend to divide more often and the telomeres become very short. Measuring telomerase may be a way for detecting cancer. If scientists can discover how to stop telomerase, there is a possibility of them being able to fight cancer by making cancer cells age faster and die. If telomerase makes cancer cells immortal, is it possible for it to prevent the normal cell aging? If this is possible there is a possibility of extending lifespan, however, scientists are not sure. In a lab setting, it has been possible to keep human cells dividing far beyond the normal limit and the cells did not become cancerous. Therefore, with further research, there is a possibility of extending the lifespan of human beings without the risk of developing cancer.
Difference Among Replication, Transcription, and Translation for Both DNA and RNA
Replication is the process of copying DNA in a cell to make two copies. This is normally done in preparation for mitosis or cell division. Replication typically copies both strands of DNA molecule in order to make two new molecules of double-stranded DNA. Replication is vital for properly regulating growth and division of cells (Hamperl & Cimprich, 2014). Transcription is described as the process of copying DNA into RNA. This results in s single-stranded product spanning only a tiny fraction of an entire DNA molecule. Transcription takes place in preparation for protein translation. Transcription is the method used for regulating gene expression. Translation is the process used by the ribosome to make protein using RNA as a template. Translation is the protein synthesis with the assistance of tRNA.


References
Hamperl, S., & Cimprich, K. A. (2014). The contribution of co-transcriptional RNA: DNA hybrid structures to DNA damage and genome instability. DNA repair, 19, 84-94.
Hennig, W. (2013). Structure and Function of Eukaryotic Chromosomes. Heidelberg, Germany: Springer.