Answers

Homework 2

Student’s Name

Institutional Affiliation

Course Tittle

Professor’s Name

Date

Answers

The discovery in the year 1953 of the dual helix, the twisted-ladder structure of deoxyribonucleic acid (DNA), by Francis Crick and James Watson created a milestone in the account of science and resulted in contemporary molecular biology, which is majorly concerned with comprehending how genetic factors control the biochemical actions within cells. The discovery of the shape of the DNA produced groundbreaking understandings into the protein synthesis and genetic code (Satyavolu et al., 2019). Throughout the 1970s and 1980s, it aided to yield novel and great scientific practices, especially genetic engineering, recombinant DNA research, monoclonal antibodies, and rapid gene sequencing techniques on which nowadays multi-billion dollar biotechnology business is established. Great current progresses in science, to be precise the mapping of the human genome, genetic fingerprinting and contemporary forensics, and the promise, yet unsatisfied, of gene psychotherapy, all have their roots in Crick and Watson’s brilliant work. The double helix’s idea has not only remodeled biology, but it also has to turn out to be a cultural representation, symbolized in visual art, sculpture, toys, and jewelry.

Chargaff’s rules articulates that the DNA from whichever species of whichever being ought to have a 1:1 stoichiometric ratio of purine and pyrimidine bases and, more precisely, that the quantity of guanine need to be equivalent to cytosine and the quantity of adenine need to be equivalent to thymine (Fariselli et al., 2020). This arrangement is found in all strands of the DNA. The Chargaff’s rules were discovered by Austrian native chemist Erwin Chargaff in the late 1940s. Erwin Chargaff projected two significant rules in his days, which were applicably termed Chargaff’s rules. The main and greatest known accomplishment was to illustrate that in natural DNA, the quantity of guanine entities is equivalent to the number of cytosine entities, and the quantity of adenine entities equivalents the number of thymine entities.

Frederick Griffith was reviewing Streptococcus pneumoniae, a bacterium that passes on a disease to mammals. He used two strains of the Streptococcus pneumoniae, a harmless R (Rough) strain, and a virulent S (Smooth) strain to show the transfer of genetic material. The R strain, which does not have the shielding capsule, is overpowered by the host’s immune system, while the S strain is bounded by a polysaccharide capsule, which shields it from the host’s immune system. In 1952, Martha Chase and Alfred Hershey placed this uncertainty to rest. They convincingly proved that DNA is the hereditary material. Chase and Hershey put into practice the T2 bacteriophage, a virus that infects bacteria, to demonstrate this fact. A virus is principally DNA (or RNA) bounded by a protein covering. To replicate, a virus needs to infect a cell and use the host cell’s mechanism to produce several viruses, a replicative development identified as the lytic cycle.

Cancer is basically an illness of mitosis. The typical checkpoints controlling mitosis are overridden or ignored by the cancer cell. Cancer starts when a particular cell is changed or transformed from an ordinary cell to a cancer cell. Faults in mitosis result in the creation of daughter cells with too few or too many chromosomes, a feature called aneuploidy. Almost all aneuploidies that result due to faults in meiosis or in the course of early embryonic development are fatal, with the distinguished exemption of trisomy 21 in humans (Levine & Holland, 2018). Mitotic mistakes can activate the triggering of p53. Errors in cell division normally lead to triggering of the cancer suppressor protein p53, which inline prompts a cell cycle apoptosis or senescence.

Turner syndrome is caused when the condition outcomes from monosomy X. The chromosomal disorder happens as an unsystematic occurrence during the development of generative cells, including eggs and sperm in the pretentious individual’s parent. A cell division mistake known as nondisjunction can predict outcomes in reproductive cells with an irregular quantity of chromosomes. Mistakes can happen all through meiosis generating gametes with missing or an extra chromosome. The results of this subsequent fertilization rely on the chromosomes that are affected. Frequently the embryo is not feasible, but several of these mistakes can result in sex chromosome disorders or trisomy disorders. 

Polyploidy is the existence in cells of more than a particular duo of each chromosome. It may be the consequence of an unprompted increase of a plant’s hereditary material or by hybridization and is very common in domesticated plants. This condition comes as a result of the complete nondisjunction of chromosomes in the course of meiosis or mitosis. It is more common in crops and has been, in reality, the main source of speciation in the angiosperms. Principally significant is allopolyploid, which implicates the replication of genetic material in a hybrid plan.

Reference

Fariselli, P., Taccioli, C., Pagani, L., & Maritan, A. (2020) DNA sequence symmetries from randomness: the origin of the Chargaff’s second parity rule. Briefings in Bioinformatics

https://doi.org/10.1093/bib/bbaa041Levine, M. S., & Holland, A. J. (2018) The impact of mitotic errors on cell proliferation and tumorigenesis Genes & development, 32(9-10), 620-638

Satyavolu, N. S. R., Loh, K. Y., Tan, L. H., & Lu, Y. (2019) Discovery of and insights into DNA “codes” for tunable morphologies of metal nanoparticles Small, 15(26), 1900975

https://doi.org/10.1002/smll.201900975