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DNA Questions and Answers (Q&A)

The correct answer is the Punnett square. The chart that shows the possible gene combinations is called a punnet square. It is a square diagram that is used to represent the possible genotype of offspring from their parents. The tool represents a visual representation of Mendel’s experiment. This square diagram was devised by an English Scientist, Reginald C. Punnett, in the twentieth century, and it was named after him.

Punnett square is commonly used by biologists and scientists to determine the genotype of offspring. The Punnett square gives all the possible genetic outcomes of what two individuals will produce when crossed. It is one of the easiest ways to calculate the probability of inheriting a particular trait. Punnett square can be set up easily by drawing a grid of perpendicular lines then put one parent genotype cross the top and the other on the left side.

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The acronym PCR stands for Polymerase Chain Reaction. PCR is a popular lab technique that is used to make multiple copies of a particular segment of DNA in vitro (inside a test tube instead of an organism). It was developed by Kary Mullis in 1983. PCR occurs in 3 stages. These stages are denaturation stage, annealing stage, and elongation (extension) stage.

The denaturation stage is the first stage. At this stage, the temperature is increased to about 92 degrees Celsius. The heat helps break hydrogen bonds between DNA strands. In the annealing stage, the temperature is reduced to 55 to 65 degrees Celsius to allow primers to bind the complementary sequence on template DNA. In the last stage, the temperature is raised again to 72 degrees Celsius to allow the synthesis of new DNA strands.

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The correct answer is option C – James Watson, Francis Crick, and Maurice Wilkins. The Double Helix structure of DNA was first described by James Watson, Francis Crick, and Maurice Wilkins. The double helix structure was first described in 1953. James, Crick, and Wilkins were awarded a Noble Prize in Medicine in 1962 for this discovery.

However, there was someone else that contributed to this discovery that wasn’t acknowledged. Rosalind Franklin was not recognized for her contribution. She died before the Noble price was won. She died of ovarian cancer at the age of 37. This discovery is one of the most significant discoveries of mankind. The double helix structure of DNA shows the two linear strands of DNA that run opposite to each other and twisted together. These strands are held together by chemical bonds.

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The correct answer to this question is option D – Reduced transcription rates because nucleosomes occupy promoters. Histone acetyltransferase, commonly known as HATs, are enzymes that acetylate histones on DNA. HATs work by transferring acetyl group lysine amino acid that is present of histone. Acetylation of histones on DNA usually causes gene expressions as this allows transcription factors to bind easily to regulatory sites such as promoter regions on the DNA.

In this child, Histone acetyltransferase is deficient. This makes histone remain tightly bound to DNA, and the nucleosome (DNA with histone) remains unchanged, making it impossible for regulatory sites to be occupied by transcription factors. This will ultimately lead to a reduced rate of transcription.

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Bruh its mot anaphase is suppose to be metaphase cause the other question was the same thingggggg

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The correct answer to this question is option C – Translocation. From the analysis above, we can tell that the process in protein synthesis that is inhibited by the new antibiotics is translocation. Translocation is the process that occurs in the elongation phase of translation (protein synthesis). During translocation, the mRNA-tRNA moiety is advanced on the ribosome to the next codon to be on the decoding area.

If translocation is blocked, the mRNA-tRNA moiety remains on the decoding center on the ribosome, and this will be the only product present. This is typical of the analysis above; we can tell that the only product made was methionyl-phenylalanyltRNA (the mRNA-tRNA moiety). Blockage of initiation (option B), the formation of the peptide bond (option D), and blockage of the binding of an aminoacyl tRNA to the A site of the ribosome will not cause this to happen.

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The correct answer is option E – Creates a short RNA primer complementary to the DNA template. DNA primase is an enzyme that plays a vital role in DNA replication. It is a type of RNA polymerase primase that synthesizes a short sequence of RNA known as primers. Primers serve as the starting point of DNA synthesis in DNA replication.

This initial step is important because DNA polymerase (an enzyme that synthesizes DNA) can synthesize new DNA nucleotides to an already existing nucleotide. The primer serves as the existing g strand of nucleotide in DNA elongation. After the elongation process, the short sequence RNA primer is removed by 5’to 3’ exonuclease, and the region is filled then filled with DNA.

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The correct answer to the question is option B – When a high temperature is maintained before polymerase is added (reduces nonspecific primer binding). A hot start is a form of modification of traditional Polymerase Chain Reaction (PCR). It is one of the most advanced modifications of PCR. In the hot start, DNA polymerase is inactivated at low temperatures, which avoid nonspecific amplification of DNA.

Nonspecific binding was a major cause of concern in PCR because of the possible mispriced of a false prime target. This caused an increase in false results. Hot start prevents the nonspecific binding step, and this leads to a reduction information of primer dimmer and nonspecific priming. At the end of it all, the hot start will lead to better and increase product yield.

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The correct answer to this question is option C – The partial charges are not opposites, so no hydrogen bonds can form. The oxygen and nitrogen present in nitrogenous bases are electronegative atoms. Electronegative oxygen and nitrogen atoms that have free lone pair have potential of accepting hydrogen bonds (hydrogen bond acceptors). DNA nucleotides have the potential to form hydrogen bonds will complementary nucleotides.

For instance, guanine and cytosine form nitrogenous base pair because of their complementary (3) hydrogen bond donor and hydrogen bond acceptors. This makes both nucleotides complementary to one another. Same goes for adenine and thymine, they pair by hydrogen bond donors and acceptors. They have only 2 hydrogen bonds between them.

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The correct answer to this question is option D – It can ACT as an exonuclease to cut single stranded DNA Taq DNA polymerase also as Taq pol is a DNA polymerase commonly used in PCR to amplify segments of DNA. The optimal level of activity of Taq pol is seen at approximately 72 degrees Celsius.

This means it functions at extremely high temperature (option A). It functions to add nucleotide triphosphates to form a new DNA strand (option B). For Taq pol to work, PCR must be done in a buffer (salt) environment. This help create a suitatable chemical environment for Taq pol to function (option C) Taq pol does not have 3’ to 5’ exonuclease activity. It only exhibits 5’ exonuclease activity.

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