A Study On The Lac Operon - 1332 Words

Charisse Young Bio 121 Section PR 12/7/14 Question #1. The lac operon is a clustered group of related genes that are transcribed as a single unit. These genes produce the enzymes to break down the sugar lactose in prokaryotes. Trp operon also in E. coli contains genes that codes for enzymes that produce tryptophan. Both the lac operon and the trp operon can act negatively and positively in controlling transcription. The lac operon is regulated by a repressor protein that blocks transcription from occurring. The trp operon is regulated by the trp repressor protein that binds to the operator and blocks transcription. Positive control that stimulates transcription is done by the protein activators. This positive control increases the frequency of the production of more proteins and more enzymes which equals more gene expression. The repressor proteins produces less proteins, less enzymes and equals less gene expression. Question #2. Proteins interact with DNA through the major groove. Scientist have discovered that it is unnecessary for the helix to unwind for proteins to distinguish one DNA sequence from the other. The major groove of the double helix is where proteins bind to interact with the base pairs. The major groove is defined as the larger of the two grooves in a DNA helix, where the paired nucleotides’ hydrogen bonds are accessible. DNA-binding motifs are three-dimensional structures that are found in proteins. These motifs are inserted into theShow MoreRelatedChapter 13 Review9122 Words   |  37 Pagesof mammalian development. false 3 RNA polymerase can bind to the promoter region of the DNA even when the lac repressor is bound to the operator site. true Hide 4 Both eukaryotes and prokaryotes require a promoter region for gene transcription. true 5 Eukaryotic genes are almost always organized in groups, similar to operons in prokaryotes. false Advertisement Hide ads ($1). 6 Unmethylated CpG islands are correlated with inactiveRead MoreBiology : Evolution, Energy, Information, And Systems1436 Words   |  6 PagesBiology, the study of life and living organisms, is complex and encompasses a multitude of theories and ideas. In AP Biology, the fourth unit covered was genetics. Chapters 11, 12, 13, 14, 15, 16, and 18 in the textbook, Campbell’s Biology in Focus, not only discusses the four main ideas of biology: evolution, energy, information, and systems, but it also gives examples of each in order to help guide the reader’s understanding of the concepts. The first big idea of AP Biology is: â€Å"the processRead MoreSalmonella Bacteria For Producing Protein Of Interest And Rate Growth And Protein Concentration After Inoculate The E.coli Culture1137 Words   |  5 Pageshigher cost, difficult optimization of media, and very low yield of the desire protein [4,8 and 10]. In bacteria, such as E. coli, operon codes include the expression of three separate enzymes needed for lactose metabolism. Prior to the operon a regulatory gene continually makes repressor proteins that bind with the operator thus restrain the transcription of the operon. Indeed, the system remains off until lactose molecules bind to the repressors and prevents their attachment to the operator. OnceRead MoreCauses Of Biofilm Formation1317 Words   |  6 Pages The primary investigators of the research study include Sana S. Dastgheyb, Amer E. Villaruz, Katherine Y. Le, Vee Y. Tan, Anthony C. Duong, Som S. Chatterjee, Gordon Y. C. Cheung, Hwang-Soo Joo, Noreen J. Hickok and Michael Otto. The locations at which the studies were conducted include the institutions that each author is associated with. Those include the National Institute of Allergy and Infectious Diseases at Bethesda, Maryland and the Thomas Jefferson University located in PhiladelphiaRead MoreScientific Article Analysis1739 Words   |  7 Pagesinterest to this scientific investigation is the wide spread antibiotic resistance of S. aureus; infections subsequent to joint reconstructions and replacements can lead to amputations, systemic infections, and death. The authors of the present study recently showed that the extreme resistance of S. aureus to antibiotics reflects pronounced biofilm formation and bacterial agglomeration. Presumbably, the antibiotic cannot reach its potential target. As these agglomerates of cells increase in sizeRead MoreSynovial Bacterial Lab1770 Words   |  8 Pagesof PSMs; l. Statistics. C. What are the general results/conclusions from the study? a. Their findings suggest that therapeutic strategies against staphylococcal PJI should target the host-derived and bacterial factors that contribute to agglomerate, such as fibrin and bacterial biofilm matrix molecules, including PIA. INTRODUCTION 3. A. Describe any important background research/information important to the study. a. Staphylococcus aureus is a major cause of septic arthritis and orthopedicRead MoreConjugation and Transposition in Escherichia Coli2748 Words   |  11 PagesAbstract The purpose of this experiment was to study the transfer of genetic information on plasmid F’lac by using Escherichia coli. Plasmid transfer was measured by using two different methods. The first one was by using selection and contraselection with three antibiotics: streptomycin(which was replaced by naladixic acid for the second part of the experiment),ampicillin and kanamycin and the second one by using a colour indicator ( X-gal). As significant results, the percentage of transfer forRead MoreBiological Molecules Like Nucleic Acids And Polysachharides2245 Words   |  9 Pagesdiscover and determine different biological pathways (Anderson, 2005). The main perseverance of molecular biology is to study life but at molecular level. As proteins are involve in important life processes so production of these proteins is very important at industrial level. Proteins have been studied and analysed in their purified form. Many molecular techniques have been used to study proteins t o know their structure and function. The function of proteins is described by the structure. The three-dimensionalRead MoreThe Use Of Bacteria For Recombinant Protein Production1283 Words   |  6 Pagesapplied with UV light. In the arabinose gene expression operon, genes are controlled by the use of plasmid cloning vectors ara (arabinose) promoter and the lac (lactose) structural genes, which were created for the recognition and analysis of signals which are responsible for gene transcription. Expression of the lac genes in the absence of the inducer arabinose indicates that transcription originates within the inserted fragment; non-expression of lac with arabinose present indicates that transcriptionRead MorePhenol-Soluble Modelins In Synovial Flu-Sb Case Study1261 Words   |  6 Pagessurface attached proteins such as fibrin which is available in the infected joint due to its role recovery of injured tissues. They found that bacteria mutants that cannot utilize fibrinogen were unable to form the macroscopic complexes. In this study, they focused on finding a mechanistic way that S. aureus forms these ex-tremely large biofilms in synovial fluid by testing altered expressions of specific bacterial factors. They also tested the Agr gene and PSM’s roles in formation of biofilms.

Essay on The Naïve Man in ohn Steinbeck’s Of Mice and Men

Innocence is a theme that few people in the world possess. In the times of John Steinbeck’s novel Of Mice and Men, written in 1937 innocence was an even rarer trait than today. However Lennie is one of those few whose innocence was preserved throughout the novel. Because of his immature traits like Childish behavior, naivety, and devotion Lennie goes on to be one of the strongest moral characters in the novel Of Mice and Men. Lennie is very childish throughout this story. For a grown man Lennie has proven to be the most childish. In chapter one when Lennie and George are walking to the ranch, they decide to stop and have a drink. While Lennie is bent down to drink he notices his splashing makes ripples in the water. â€Å"Lennie dabbed his big†¦show more content†¦He thinks that he can yell at her and she will wake up, when that fails he decides to hide her body under some straw and runs for his hiding place. Lennie doesn’t understand what he has done wrong, or that he even did anything wrong. Through this Lennie shows how truly naà ¯ve he can be through his inappropriate actions. Not all of Lennie’s traits are detestable as Lennie also possesses the trait of devotion, a very admirable trait. Lennie proves time and again in Of Mice and Men how devoted he is to his brother-like friend, George. As stated previously, Lennie is a very childish and naà ¯ve individual making him slow to anger. That is why it is so remarkable the intensity of the anger and almost malice he has towards Crooks when he threatens the one person Lennie is devoted to most, George. â€Å"Lennie’s eyes centered and grew quiet and mad. He stood up and walked dangerously towards crooks. ‘Who hurt George?’ He demanded.† (Steinbeck 72). In just a short period of time Lennie went from a calm talk to Crooks to a near brawl over a â€Å"what if† scenario that had not even happened to George. Lennie would have fought to protect the person he puts on a pedestal. While Lennie is not the brightest character he does prove his devotion to George time and again. L ennie is an ingenuous man, innocent in all of the ways in the world. Due to him being slightly slower than others because of a

How is Benedick presented in the scenes leading up to this point Free Essays

In these two extracts, Shakespeare provides two very different presentations of Benedick. The first: misogynistic, marriage-fearing Benedick which he projects to his audience. Second: the warm-hearted, love-sick Benedick who, despite his fiery demeanour, is very much in love with Beatrice. We will write a custom essay sample on How is Benedick presented in the scenes leading up to this point? or any similar topic only for you Order Now In the first part, Benedick soliloquises about the man who â€Å"dedicates his behaviours to love† is a fool, and the irony of becoming the â€Å"argument of his own scorn.† This pre-empts the drastic change in Benedick’s behaviour later in the scene. Already we see a confident flurry of long, complex declaratives, signalling a kind of gusto to Benedick’s emotions: he clearly feels strongly about this issue. However, the fact that he must say these things to himself may serve to highlight his insecurity with himself. It is quite obvious from earlier points in the play that Benedick is wholly uncomfortable with his feelings towards Beatrice and tries (unsuccessfully) to hide these feelings. In the next few lines, Benedick contrasts battle imagery such as â€Å"good armour† with softer, more romantic objects, such as a â€Å"new doublet.† This serves to illustrate his contempt for Claudio’s utter turnaround. His tripling in this section further emphasises both Benedick’s views, and indeed his own issues. The fact that he must use persuasive techniques such as parallelism suggests that he himself cannot truly bring himself to believe his apparent viewpoint. Benedick ends with a long list of characteristics which he wishes to see in his dream woman. Although utterly fantastic in terms of realistic prospects, it nevertheless contrasts with Benedick’s view earlier in the narrative, where he insists that he will â€Å"die a bachelor.† His dogmatic disposition is obviously being broken down in small steps. The comment suggests that Benedick is not as opposed to the notion of taking a woman as he may be trying to convey; it is more a reluctance to settle for less, as it were. As we shall see, Beatrice proves to be this catalyst for his transformation. The second extract follows the planting of the idea that Beatrice is in love with Benedick into his mind, by Don Pedro, Claudio and Leonato. Once again, Benedick launches into an excitable monologues, consisting of a few very long declaratives. This certainly displays a lot of excitement on his part, and the fact that he uses an interrogative, a rhetorical question (â€Å"love me?†), shows a disbelieving sense of glee and does much to counteract the pessimistic Benedick from a few lines earlier. In conjunction with his earlier soliloquy, Benedick attempts to dismiss his earlier ideas, stating that â€Å"a man loves the meat in his youth, that he cannot endure in his age.† He seems to think that it is acceptable that he can change his views drastically over the space of a few minutes without any sort of continual repercussions. His metaphor serves as a hyperbolic piece of irony, the imagery not befitting the very short space of time that Benedick is describing. As Beatrice enters, we see Benedick misinterpreting her words in a very optimistic manner. He believes that her words truly confirm her feelings for him and fails to see the absurdity of his thoughts. The transformation, if you will, is complete. Benedick even goes so far as to recite some of the qualities listed and how they are apparent in Beatrice. Again, the use of tripling is effective, but here instead to show a rush of revelationary excitement that his slim hopes have been realised. Overall, the second extract serves to prove the insecurity conveyed in the first. Shakespeare presents Benedick as unsure and unnecessarily dogmatic, and this is confirmed by his behaviour in the second part. In the scenes leading up to this, we see the establishment of Benedick as the witty cynic, at odds with traditional values. I believe that Shakespeare’s initial presentation of Benedick goes in stark contrast to his true character. In the first scene, he is called â€Å"a good soldier.† The later war of wits with Beatrice, and his misogynistic advice to Claudio and Don Pedro very much establishes Benedick as a â€Å"man’s man,† if such a thing existed in Elizabethan times. However, I believe that this is merely a faà ¯Ã‚ ¿Ã‚ ½ade, and that he does have a pretty clear motive. It seems to me like the reason for Benedick’s disposition is, put simply, Beatrice. He is confused and frustrated at his feelings towards Beatrice, and attempts to counteract them through his words of scorn. Quite clearly, the other characters see through this, and this is what leads them to trick him later. Another aspect of Benedick’s personality, his insecurity, also seems to stem from Beatrice. At the party scene, he shows exasperation at her description of him as a â€Å"jester† and â€Å"dull as a great thaw.† Benedick clearly cares about Beatrice’s opinion of him, no matter what his exterior may suggest. His short monologue at the end of that scene is once again one where interrogatives are used in order for Benedick to reassure himself. Benedick is seen to have a sharp-tongued speaking style interspersed with witty metaphors and riddles. This singles Benedick out of someone with a high level of intelligence, but it also immediately identifies him as a counterpart to Beatrice. His militant anti-marriage stance is mirrored by hers, and his words of advice to Claudio convey his emotions in flowery prose, perhaps suggesting a reluctance to disclose any true information about himself. Overall, Benedick is presented as someone who is heavily influenced by Beatrice, and it seems that it is her actions that shape his personality, and define him as a character. Obviously, this is consistent with the narrative, and goes a long way to explain Benedick’s sudden change of heart in Act 2 Scene 3. How to cite How is Benedick presented in the scenes leading up to this point?, Papers