During the 8 weeks of this course, you have been learning about genes and their

Question

During the 8 weeks of this course, you have been learning about genes and their role in inheritance – the way certain traits are passed down from one generation to another. Based on your readings from the textbook and on our weekly discussions, you will write an APA formatted, 1000-word paper, that addresses the following four questions:

How does the structure of DNA (double helix) determine how the genetic information is passed on?

How does the cell use the information contained in the DNA to construct proteins (transcription and translation)?

How is gene expression regulated (give three different forms of regulation mechanisms)?

How does gene regulation relate to cancer development?

Explanation / Answer

DNA carries the code for a particular protein.Genes control the development of different characteristics of an organism.Genes carry all the genetic information for organism. Chromosome contain many genes.Number of genes and chromosomes varies from species to species.Cells in human beings have 46 chromosomes that carry about 30,000 genes in each cell; and cells in fruit flies have eight chromosomes that carry about 13,600 genes.

mRNA formed in transcription is transported into the cytoplasm, to the ribosome (the cell's protein synthesis factory).Process by which mRNA creates protein synthesis with tRNA is called translation.Ribosome is a very large complex of RNA and protein molecules.Transcription and translation are separated in eukaryotic cells.In eukaryotes, transcription and translation take place in different cellular compartments: transcription takes place in the nucleus, whereas translation takes place outside ,in the cytoplasm. In prokaryotes, the two processes are closely related.

Regulation of gene expression includes a wide range of mechanisms that are used by cells to increase or decrease the production of specific gene products (protein or RNA), and is informally termed gene regulation. Sophisticated programs of gene expression are widely observed in biology, for example to trigger developmental pathways, respond to environmental stimuli, or adapt to new food sources. Virtually any step of gene expression can be modulated, from transcriptional initiation, to RNA processing, and to the post-translational modification of a protein. Often, one gene regulator controls another, and so on, in a gene regulatory network.Gene regulation is important for viruses,prokaryotes and eukaryotes as it increases the versatility and adaptability of organism by allowing the cell to express protein. In early 1951,Barbara McClintockshowed interaction between two genetic loci, Activator (Ac) and Dissociator (Ds),for the color formation of maize seeds,first discovery of a gene regulation system is widely identified in 1961 in the lac operon, discovered by François Jacob and Jacques Monod, in which enzymes involved in lactose metabolism are expressed by E. coli only in the presence of lactose and absence of glucose.In multicellular organisms, gene regulation creates cellular differentiation and morphogenesis in the embryo,which leads to creation of different cell types that possess different gene expression profiles from same genome sequence. This explains how evolution actually works at a molecular level, and is center of the science of evolutionary developmental biology.The event that leads to a change in gene expression includes activation or deactivation of receptors.

Cancer is described as disease of altered gene expression. There are many proteins that are turned on or off that alters the activity of the cell.Gene that is not normally expressed in that cell can be switched on and expressed at high levels. This can be the result of gene mutation or changes in gene regulation ( epigenetic, transcription, post-transcription, translation, or post-translation).Transcription, RNA stability, protein translation, and post-translational control can be detected in cancer. Changes do not occur simultaneously in one cancer, changes observing cancer at different sites in different individuals. Changes in histone acetylation (epigenetic modification that leads to gene silencing), activation of transcription factors by phosphorylation, increased RNA stability, increased translational control, and protein modification can be detected at some point in various cancer cells. Scientists are working on how to understand the common changes that give rise to certain types of cancer or how a modification is done to destroy a tumor cell.

Related Questions

Navigate

• Browse (All)
• Browse D
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.