Genes include the recipes for proteins without which the existence of life ought to not be possible. The chemical structure and form of the protein dictate its function as either a hormone, a catalyst, power storage, transportation or other functions that are crucial to the existence of life. The proteins are known to be both catalysts and end-goal of gene expression. Gene expression refers to the phenotypic gene manifestation thru the processes of genetic translation and genetic translation. Expressed genes results to the genetic data found in the DNA being copied to a mRNA (transcription). The latter then leave the phone nucleus consequently entering the cytoplasm. At this place, they take part in the synthesis of protein through the specification of specific amino acids comprising of the individual proteins (translation). The process of transcription refers to the production of an RNA molecule using DNA template. According to Pelechano, Wei & Steinmetz, (2015), the RNA upon maturity and exciting the nucleus can then be changed to polypeptide sequence through a process called translation. It is worth noting that in the nucleoid region in the majority of bacterial species there are circular DNA molecules called plasmids in addition to the chromosomes (Kreuzer, 2013).
Proteins are considered to be the end-product of the process of gene expression in addition to regulating translation and transcription by acting as enzymes (Holoch & Moazed, 2015). The process of transcription forms the first step of gene expression. Upon a gene being transcribed, its double-stranded DNA is unwound by enzymes thereby reading the DNA and copy the information contained leading to the production of RNA messenger (mRNA). The finish point is when the mRNA is rewound. Translation process then involves the transferring the transcribed information into an amino acid chain through a different enzyme.
The importance of gene expression lies in the fact that the process results in the phenotype leading to the observable trait. Hence the gene expression acts as an interpreter of the genetic code that has been stored in the DNA. The synthesis of controlling proteins in the organism’s shape is thus important in as far as the development of the organism is concerned. The purpose of the experiment “Gene expression” is to allow for the observation of the process of bacterial transformation in addition to demonstrating the relationship between the constituents of genes of organisms and their physical attributes. Hence assisting in comprehending how phenotypes can be expressed as well as being controlled.
The questions to be answered towards the completion the experiment, therefore, are as follows:
1. How does gene expression occur through the processes of transcription and translation?
2. How does gene expression regulation occur and what are its effects on the phenotype of organisms involved?
The experiment, therefore, has the importance of explaining the process of gene expression involving translation and transcription. The knowledge of the process of gene expression and its control regulation will, therefore, assist in understanding growth and development of organisms. In addition to that, the knowledge will result in the understanding of both recycling and replacement of cells in the body of organisms during the process of growth and development.
This section looks at the results upon the completion of the experiment and then comparing them with the expectations. In addition to that, it provides reasons for similarity or the differences as encountered in the results.
The results arrived at in the experiment
Upon finalizing of the experiments there were observations that were made where the majority were like the expectations. For example, the bioluminescence had positive results in comparison to the expectations with the first four having no observation of bioluminescence and the last two had a positive observation. The observed growth had positive results in comparison to the predictions made. The predictions, however, did not specify the type of growth expected but in the results, the types of results were recorded as either lawn or colonial growth.
The reasons that were provided, however, were not matching in some cases. For example, the predictions had most reasons for most of the experiments as being so because of either the presence or absence of plasmid. It is only in the last part that the prediction has indicated to have no antibiotic. On the other hand, the results from the lab gave reasons that mainly cited the absence of antibiotic and the restrictions of growth by ampicillin contrary to the predictions.
Reasons for the results
The significance of the explanations of the result helps in the understanding of the different observations in the experiment. In addition, it helps in the comparison of the predictions in relation to the real results arrived. Hence it will allow for identifying the source of error if any that was encountered.
The reasoning provided in the experiment though not consistent with the predictions, they revolve around the plasmid either present or absent. First, we need to know the why bacteria carry the plasmid. Firstly, they contain useful genes and they can transfer between bacteria easily than the chromosome. The observations that showed negative results for the existence of bioluminescence essentially had no plasmid. And due to this fact, they could not result in positive observations of bioluminescence.
The nature of growth in the results (either colonial or lawn) can be attributed to the population of the bacteria. The lawn growth implied that the bacteria were many in comparison to the situation where there was a colonial growth. For example, in the reasoning in the first experiment there was the lawn growth and the reasoning provided was that there was no antibiotic. The absence of the antibiotic meant that the environment was conducive for the bacteria to thrive as there was nothing available to disrupt their existence. On the other hand, the colonial growth has a reason that the ampicillin restricted the growth. The implication that the ampicillin was responsible for the restriction of the growth seems to be okay. The reason being that the restriction was not on the entire bacteria and so the ones that managed to flow did so but in a scattered manner hence resulting to colonial growth. The colonial growth, therefore, implies that there were less favorable conditions for the growth of the bacteria.
The importance of the plasmid, therefore, is that they can allow us to transfer genes of our interest to bacteria with an aim of them expressing their protein in large amounts. This revolves around the process of gene expression. In general, this is the process of gene expression regulation where the desired characteristics are prioritized hence it assists in coming up with the right organism in terms of the desired traits.
Answering of the experiment question by the experiment
The answering of the first experimental question was done correctly given that most of the predictions based on the theory were met with the only difference in the giving reasons for the observations for the predictions and the results. However, the answering of the second question was not fully done in the experimental part. Looking at the first question the answering of the question was done to due to the expectations being met with the results. The second question, however, was not fully catered for because the aspects of phenotype were not well represented in the results. The redesigning of the experiment needs to be done in order to ensure that the question is well taken care of. For example, in the case of the second question, the experiment needs to be redesigned to have the aspects of phenotype incorporated in the process of getting the results.
From the above experiment, we have seen the concept of gene expression in both theoretical and experimental perspective. The theoretical has given the general outline of the process regarding transcription and translation. On the other hand, the experimental part has given the expression actual process through the use of bacteria. The results in comparison with the predictions have shown that the experiment was done appropriately and responded to the research question as required. The part of the research question that was not well answered well, therefore, calls for adjustment of the experiment to accommodate the question. Generally, the experiment was a success and has provided some insight into the knowledge about gene expression.
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Kreuzer, K. N. (2013). DNA damage responses in prokaryotes: regulating gene expression, modulating growth patterns, and manipulating replication forks. Cold Spring Harbor perspectives in biology, 5(11), a012674.
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Pelechano, V., Wei, W., & Steinmetz, L. M. (2015). Widespread co-translational RNA decay reveals ribosome dynamics. Cell, 161(6), 1400-1412.
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