Genetic Analysis: An Integrated Approach (2nd Edition)
2nd Edition
ISBN: 9780321948908
Author: Mark F. Sanders, John L. Bowman
Publisher: PEARSON
expand_more
expand_more
format_list_bulleted
Concept explainers
Videos
Textbook Question
Chapter 12, Problem 11P
Two different mutations are identified in a haploid strain of yeast. The first prevents the synthesis of adenine by a nonsense mutation of the
Do you consider the first mutation to be a forward mutation or a reversion? Why?
Do you consider the second mutation to be a forward mutation or a reversion? Why?
Assuming there are no other mutations in the genome, will this double
Expert Solution & Answer
Trending nowThis is a popular solution!
Students have asked these similar questions
Several experiments were conducted to obtain information about how the eukaryotic ribosome recognizes the AUG start codon. In one experiment, the gene that encodes methionine initiator tRNA (tRNAiMet) was located and changed; specifically, the nucleotides that specify the anticodon on tRNAiMet were mutated so that the anticodon in the tRNA was 5′ –CCA–3′ instead of 5′ CAU–3′. When this mutated gene was placed in a eukaryotic cell, protein synthesis took place, but the proteins produced were abnormal. Some of these proteins contained extra aminoacids, and others contained fewer amino acids than normal.
a. What do these results indicate about how the ribosome recognizes the starting point for translation in eukaryotic cells? Explain your reasoning. b. If the same experiment had been conducted on bacterial cells, what results would you expect? c. Explain why some of the proteins produced contained extra amino acids while others contained fewer amino acids than normal.
Several experiments were conducted to obtain information about how the eukaryotic ribosome recognizes the AUG start codon. In one experiment, the gene that encodes methionine initiator tRNA (tRNAiMet) was located and changed; specifically, the nucleotides that specify the anticodon on tRNAiMet were mutated so that the anticodon in the tRNA was 5′ –CCA–3′ instead of 5′ –CAU–3′. When this mutated gene was placed in a eukaryotic cell, protein synthesis took place, but the proteins produced were abnormal. Some of these proteins contained extra amino acids, and others contained fewer amino acids than normal.
Q. What do these results indicate about how the ribosome recognizes the starting point for translation in eukaryotic cells? Explain your reasoning.
Several experiments were conducted to obtain information about how the eukaryotic ribosome recognizes the AUG start codon. In one experiment, the gene that encodes methionine initiator tRNA (tRNAiMet) was located and changed; specifically, the nucleotides that specify the anticodon on tRNAiMet were mutated so that the anticodon in the tRNA was 5′ –CCA–3′ instead of 5′ –CAU–3′. When this mutated gene was placed in a eukaryotic cell, protein synthesis took place, but the proteins produced were abnormal. Some of these proteins contained extra amino acids, and others contained fewer amino acids than normal.
Q. If the same experiment had been conducted on bacterial cells, what results would you expect?
Chapter 12 Solutions
Genetic Analysis: An Integrated Approach (2nd Edition)
Ch. 12 - 11.1 Identify two general ways chemical mutagens...Ch. 12 - 11.2 Nitrous acid and (BU) alter DNA by different...Ch. 12 - 11.19 Using the adeninethymine base pair in this...Ch. 12 - The partial amino acid sequence of a wild-type...Ch. 12 - 5. Thymine is usually in its normal, common form....Ch. 12 - Ultraviolet (UV) radiation is mutagenic.
What...Ch. 12 - Researchers interested in studying mutation and...Ch. 12 - The effect of base - pair substitution mutations...Ch. 12 - Prob. 9PCh. 12 - 11.10 In numerous population studies of...
Ch. 12 - 11.11 Two different mutations are identified in a...Ch. 12 - 11.22 Many human genes are known to have homologs...Ch. 12 - 11.13 Answer the following questions concerning...Ch. 12 - Prob. 14PCh. 12 - Prob. 15PCh. 12 - Prob. 16PCh. 12 - 11.15 A sample of the bacterium is exposed to...Ch. 12 - 11.16 A strain of is identified as having a null...Ch. 12 - Define gene conversion and contrast it with gene...Ch. 12 - Prob. 20PCh. 12 - Prob. 21PCh. 12 - Prob. 22PCh. 12 - Prob. 23PCh. 12 - Prob. 24PCh. 12 - 25. If homologous recombination did not occur,...Ch. 12 - In this chapter, three features of genes or of DNA...Ch. 12 - Briefly compare the production of DNA double -...Ch. 12 - During mismatch repair, why is it necessary to...Ch. 12 - 11.27 Following the spill of a mixture of...Ch. 12 - A geneticist searching for mutations uses the...Ch. 12 - A wild - type culture of haploid yeast is exposed...Ch. 12 - A fragment of a wild - type polypeptide is...Ch. 12 - Prob. 33PCh. 12 - 11.40 Common baker’s yeast () is normally grown at...Ch. 12 - 11.41 The two gels illustrated below contain...Ch. 12 - Alkaptonuria is a human autosomal recessive...Ch. 12 - 11.33 In an experiment employing the methods of...Ch. 12 - Using your knowledge of DNA repair pathways choose...Ch. 12 - 11.35 Ataxia telangiectasia is a human inherited...Ch. 12 - 40. Two haploid strains of fungus are fused to...
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, biology and related others by exploring similar questions and additional content below.Similar questions
- Several experiments were conducted to obtain information about how the eukaryotic ribosome recognizes the AUG start codon. In one experiment, the gene that encodes methionine initiator tRNA (tRNAiMet) was located and changed; specifically, the nucleotides that specify the anticodon on tRNAi Met were mutated so that the anticodon in the tRNA was 5′ –CCA–3′ instead of 5′ –CAU–3′. When this mutated gene was placed in a eukaryotic cell, protein synthesis took place, but the proteins produced were abnormal. Some of these proteins contained extra amino acids, and others contained fewer amino acids than normal. a. What do these results indicate about how the ribosome recognizes the starting point for translation in eukaryotic cells? Explain your reasoning. b. If the same experiment had been conducted on bacterial cells, what results would you expect? c. Explain why some of the proteins produced contained extra amino acids while others contained fewer amino acids than normalarrow_forwardConsider the now dominant variant of the SARS-CoV-2 called the D614G mutation: a) The mutation changes an Aspartate (D, Asp) to a Glycine (G, Gly) at nucleotide position 614 (that’s why it’s called the D614G mutant) in the S1 subunit of the Spike protein. Using only the information above and a codon table, what are the mRNA codon sequences of the 2019-dominant and 2020-dominant Spike proteins? Note the figure above is not needed toanswer the question. Report in 5’ to 3' orientation __________________________________________ b) What type of substitution is this? In your answer, address the following: • The expected substitution in base sequence (e.g., A à C)• If the mutation is synonymous, nonsynonymous, or a frameshift• If the mutation is a transition or a transversion c) The mutation increases infectivity by reducing the stability of the Spike protein such that it can remain in the open conformation more often. The open conformation increases the chances of binding to the host ACE2…arrow_forwardSeveral experiments were conducted to obtain information about how the eukaryotic ribosomerecognizes the AUG start codon. In one experiment, the gene that encodes the methionine initiatortRNA (tRNA,Met) was identified and changed. Specifically, the nucleotides that specify the anticodonon the tRNA,Met were mutated so that the anticodon in the tRNA was 5'-CCA-3'. When thismutated gene was introduced into a eukaryotic cell protein synthesis occurred, but the proteinsproduced were abnormal. Some of these proteins contained extra amino acids and others containedfewer amino acids than normal. a.) What is the normal anticodon for tRNA,Met? Show how this normal anticodon would interact with the codon for methionine in the mRNA. b.) What codon does the mutant anticodon bind? What amino acid is incorporated into the polypeptide chain? Show the interaction between the mutant anticodon and the amino acid codon and finally, What do the results described above indicate about how the ribosome…arrow_forward
- Several experiments were conducted to obtain information about how the eukaryotic ribosomerecognizes the AUG start codon. In one experiment, the gene that encodes the methionine initiatortRNA (tRNA,Met) was identified and changed. Specifically, the nucleotides that specify the anticodonon the tRNA,Met were mutated so that the anticodon in the tRNA was 5'-CCA-3'. When thismutated gene was introduced into a eukaryotic cell protein synthesis occurred, but the proteinsproduced were abnormal. Some of these proteins contained extra amino acids and others containedfewer amino acids than normal. Explain why some of the proteins produced contained extra amino acids while otherscontained fewer amino acids than normal? e. If the same experiment had been conducted in bacterial cells, what results would youexpect? Explain.arrow_forwardIn bacteria, researchers have isolated strains that carry mutations within tRNA genes. These mutations can change the sequence of the anticodon. For example, a normal tRNATrp gene encodes a tRNA with the anticodon 3′–ACC–5′. A mutation can change this sequence to 3′–CCC–5′. When this mutation occurs, the tRNA still carries a tryptophan at its 3′ acceptor stem, even though the anticodon sequence has been altered. A. How would this mutation affect the synthesis of polypeptides within the bacterium? B. What does this mutation tell you about the recognition between tryptophanyl-tRNA synthetase and tRNATrp? Does the enzyme primarily recognize the anticodon or not?arrow_forwardConsider the tryptophan codon 5′ - UGG - 3′ in the standard genetic code . Can a single base change in this codon create a synonymous mutation? Can a single base change in this codon create a nonsense codon?arrow_forward
- in a clever experiment performed in 1962, a cysteine already attached to its tRNA was chemically converted to an alanine. these “hybrid” tRNA molecules were then added to a cell- free translation system from which the normal cysteine-tRNAs had been removed. When the resulting protein was analyzed, it was found that alanine had been inserted at every point in the polypeptide chain where cysteine was supposed to be. Discuss what this experiment tells you about the role of aminoacyl- tRNA synthetases during the normal translation of the genetic code.arrow_forwardThe anticodon loop of one of the tRNA Gly molecules from Escherichia coli is as follows: a) Identify the anticodon, reading from 3’ to 5’. b) This tRNA recognizes a Gly codon. What is it? Write it from 5’ to 3’.arrow_forwardYeast have 8 similar tRNA genes with the anticodon 5’-GUA. A researcher mutates one of these genes to change its anticodon to 5’-GUU. a) What codon did the tRNA originally decode? b) What codon does the mutated tRNA decode?arrow_forward
- Yeast have 8 similar tRNA genes with the anticodon 5'-GUA. A researcher mutates one of these genes to change its anticodon to 5'-GUU. a) What codon did the tRNA originally decode? Name the amino acid. b) What codon does the mutated tRNA decode? Name the amino acid.arrow_forwarda) b) Shown below is a DNA sequence that encodes for a section of a protein. Please write the amino acid sequence using the three letter codes for this section. 5' ATG ACT CTC TCC TGG GGC ATC CGA TAA 3' What would the second codon be changed to if it was both a silent mutation and a transition mutation? Please write an anticodon in 5' to 3' direction that would recognize both the original second codon and the mutated second codon.arrow_forwardA mutation is found in a tRNA-encoding gene. The wild type (non-mutant) allele (version) produces a tRNA that recognizes the codon GAA, and is charged with the amino acid glutamic acid (Glu). The mutant tRNA is still charged with Glu, but it recognizes the codon UAA. What effect will this have on translation in these cells? How will the proteins produced be different? Speculate: is this mutation more likely to be beneficial or harmful?arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Biology (MindTap Course List)BiologyISBN:9781337392938Author:Eldra Solomon, Charles Martin, Diana W. Martin, Linda R. BergPublisher:Cengage Learning
Human Heredity: Principles and Issues (MindTap Co...BiologyISBN:9781305251052Author:Michael CummingsPublisher:Cengage Learning
Biology Today and Tomorrow without Physiology (Mi...BiologyISBN:9781305117396Author:Cecie Starr, Christine Evers, Lisa StarrPublisher:Cengage Learning
Biology (MindTap Course List)
Biology
ISBN:9781337392938
Author:Eldra Solomon, Charles Martin, Diana W. Martin, Linda R. Berg
Publisher:Cengage Learning
Human Heredity: Principles and Issues (MindTap Co...
Biology
ISBN:9781305251052
Author:Michael Cummings
Publisher:Cengage Learning
Biology Today and Tomorrow without Physiology (Mi...
Biology
ISBN:9781305117396
Author:Cecie Starr, Christine Evers, Lisa Starr
Publisher:Cengage Learning
Mitochondrial mutations; Author: Useful Genetics;https://www.youtube.com/watch?v=GvgXe-3RJeU;License: CC-BY