As we described in class, in the early 1960's Francis Crick and colleagues set out to determine how many nucleotide bases make up a codon, before it was possible to sequence DNA and before Nirenberg and his colleagues solved the genetic code. To do this, they used a chemical mutagen that they knew made single nucleotide changes, used this mutagen to conduct a screen for mutations that disrupted a particular gene, and collected a number of different mutations in this gene. Briefly describe the logic they used to deduce that the codon length is 3 nucleotides long.

Q: Early gene-cloning experiments involved insertion at one restriction site in the vector; for…

A: Answer: Introduction: Restriction endonucleases enzymes which cut DNA at precise recognition sites.…

Q: You have sequenced the genome of a new E. coli strain that you discovered during the metagenomics…

A: DNA( deoxyribonucleic acid) is the double-stranded molecule that is the genetic material in most…

Q: Name the two types of mutagens, give an example for each, and briefly describe how they cause…

A: Mutagen is a physical or chemical agent that permanently changes genetic material,usually DNA , in…

Q: List three possible uses of site-directed mutagenesis

A: BASIC INFORMATION MUTATION  It is sudden or discontinuous variation These changes occurs in the…

Q: Do you consider TEs to be mutagens? Explain.

A: Mutation is defined as sudden inheritable change that occurs in the DNA sequence. Mutation occurs…

Q: Two eukaryotic proteins have one domain in common but areotherwise very different. Which of the…

A: Eukaryotes are organisms whose cells have a nucleus enclosed within a nuclear envelope. Eukaryotes…

Q: Now that you understand how the CRISPR-Cas9 system works, think back to the experiments discussed in…

A: CRISPR-Cas9 is a genome editing tool. It helps researchers to edit or change the gene from the…

Q: A chemist synthesizes four new chemical compounds in the laboratory and names them PFI1, PFI2, PFI3,…

A: Mutations occur when there is a change in DNA due to damage which can alter the gene expression.…

Q: You have isolated a transposable element from the human genome and have determined its DNA…

A: Transposable element also known as jumping gene, is a DNA sequence which can change its position in…

Q: Which researcher started looking for mutants that affected biochemistry, and then found mutants that…

A: Thomas hunt Morgan ( T.H.Morgan) started looking for mutants that affected biochemistry, and then…

Q: Which type of mutation would expect would have no effect on a protein coding gene in eukaryotes?…

A: “Silent” mutation: doesn't change an amino acid, however in some cases will still have a…

Q: What is exon shuffling? How can it lead to the evolution of new genes?

A: Exon shuffling may be a molecular mechanism for the formation of the latest genes. it's a process…

Q: What does site-directed mutagenesis allow you to dothat normal mutagenesis does not?

A: The site-directed mutagenesis (SDM)  method allows us to create specific, targeted changes in…

Q: If you knew the mRNA sequence for the human insulin gene could you know what size cDNA fragment you…

A: It is possible to chemically synthesise a gene in the lab by laboriously joining nucleotides…

Q: Some mutations affect changes in protein structure and function that can result in disease whereas…

A: Proteins are synthesized from gene expression. They are coded by the genes and translated to form…

Q: Let’s suppose that a vertebrate organism carries a mutation that causes some cells that normally…

A: DNA is the genetic material in most living organisms. It is the information hub of the cell that…

Q: If you were examining a sequence of chromosomal DNA, what characteristics would cause you to believe…

A: Step 1 The transposable element is a DNA (deoxyribonucleic acid) sequence that can change its…

Q: Imagine that you and your colleagues are working in a lab to develop a protein synthesis system for…

A: The mRNA in prokaryotes is polycistronic, while the mRNA in eukaryotes is monocistronic.…

Q: An important validation of the genetic code occurred when George Streisinger determined the amino…

A: It is given that the specific single-base insertion mutation could be suppressed, with wild-type…

Q: Let us suppose that a vertebrate organism carries a mutation that causes some cells that normally…

A: The addition of methyl groups into DNA molecule is called DNA methylation. The activity of the DNA…

Q: You start by looking at the mutations that Yanofsky recovered in TrpA. One of these mutations…

A: Hi! Thank you for the question. As you have posted a question with multiple subparts, I will be…

Q: How many possible mRNAs could be derived from a gene with three exons (exon 1, exon 2, and exon 3)?…

A: Transcription is a process in which one strand of DNA known as template strand is known as converted…

Q: When scientists cut a eukaryotic gene from genomic DNA, they discovered that enabling the strands to…

A: Alternative splicing is a method through which a messenger RNA may control the creation of many…

Q: Expression of recombinant proteins in yeast is an important tool for biotechnology companies that…

A: Recombinant proteins are those proteins that are produced by recombinant DNA cloned in a system…

Q: How do we know that many cancer-causing agents (carcinogens)are also mutagenic?

A: A large number of chemicals and several physical agents, such as UV light and γ-radiation, have been…

Q: Some mutations affect changes in protein structure and function that can result in disease whereas…

A: Hi! Thanks for your question. But as you have posted multiple questions, I am answering the first…

Q: Why is the genome contained within a membrane?

A: A genome is a complete set of "genetic information" in an organism. It stores all of the information…

Q: What type of mutation (transition, transversion, or frameshift)would you expect each of the…

A: Mutagens are such agent that changes the genetic material, that is, the structure of DNA…

Q: Which of the following mutations would likely have the greatest negative impact on the protein…

A: Frameshift mutations are basically known as the most injurious changes to the coding succession of a…

Q: u have assembled a new prokaryotic genome and are annotating the genes.  If you were to search for…

A: Genome Annotation is a multidisciplinary process that includes genetic protein-coding prediction, as…

Q: You are interested in a eukaryotic protein involved in immunity, and you are attempting to express…

A: The question is related to the presence of introns in eukaryotic genome and its absence in…

Q: A chemist synthesizes four new chemical compounds in the laboratory and names them PFI1, PFI2, PFI3,…

A: A gene mutation is alteration in the DNA sequence  that make up the gene such that sequence differs…

Q: Now you have the gene sequence. Now you would like to clone it into an expression vector to grow up…

A: Answer. The majority of eukaryotic genes contain non-coding DNA. The genes tend to have a split…

Q: If you knew the mRNA sequence for the human insulin gene could you know what size cDNA fragment you…

A: Human insulin is a polypeptide hormone produced by insulin gene. It plays an important role in blood…

Q: Different forms of a protein are produced in the liver and in the brain by alternate splicing of its…

A: Specific mRNAs corresponding to a gene of interest must be identified and reverse transcribed to…

Q: The figure shows a Venn Diagram with four areas, Area A- Terms that only apply to eukaryotic…

A: Central Dogma is a flow of information that is present in the form of nucleotide sequence on the DNA…

Q: The Human Genome Project resulted in the identification of 20,000 genes that code for proteins in…

A: Central dogma explains the flow of genetic information from one nucleic acid to other. It involves…

Q: The CRISPR-Cas9 system may be able to be used for somatic gene therapy to treat terminal genetic…

A: Mutation: Normal DNA contains a particular sequence of DNA. If the sequence of DNA is changed due to…

Q: Which of the following mutations would have the greatest negative impact on the protein product of a…

A: Mutations are studied to understand the genetic mechanism behind the development of the disease.…

Q: You are working in the lab and are mutagenizing E. coli, to see if you can identify mutations in the…

A: Gene expression is a process by which the genes are turned on to form RNA and proteins. This is…

Q: You want to clone a eukaryotic gene and express the corresponding protein in yeast. However, the…

A: Most eukaryotic genes contain segments of coding sequences (exons) interrupted by noncoding…

Q: You obtained the sequence of the frog gene X you amplified in Question #16 through a process called…

A: A "nucleic acid" is a linear polymer of nucleotides that is a component of the cell's information…

Q: In studying the mechanism of a particular enzyme, for which the cloned gene is available, you wish…

A: Site-directed mutagenesis is the molecular biology technique that alters the sequence of the target…

Q: Let’s say, you want to deliver a gene into a cell and in your lab, there are lot of options…

A: Gene transfer: Method or process by which a gene is transferred from one DNA molecule to another.…

Q: The figure shows a Venn Diagram with four areas, Area A- Terms that only apply to eukaryotic…

A: The proteins are synthesized with the correct amino acid sequence based on instruction in DNA. This…

Q: Describe the three general groups of chemical mutagens.

A: A mutagen is a chemical or physical agent that has the capacity to change the genetic sequence in a…

Q: Which of the following is likely associated with the mRNA processing step of alternative splicing?

A: A process that helps a single gene to code for many proteins is known as alternate splicing. It is…

Q: One of these mutations affected amino acid number 177 and changed it from Leucine to Arginine –…

A: DNA and RNA are polynucleotides, i.e., they are polymers of nucleotides. DNA stores genetic…

Mitochondrial Mutations

A mitochondrion is a cellular organelle that serves as the site for cellular respiration and energy production (ATP or Adenosine Triphosphate). It is a double-membrane-bound organelle and is only present in eukaryotic cells.