Concept explainers
Identify two general ways chemical mutagens can alter DNA. Give examples of these two mechanisms.
To review:
Analyze how chemical mutagens can alter DNA. Give examples of these two mechanisms of chemical mutation.
Introduction:
Mutation can be defined as a heritable change in the DNA sequence. This change in the DNA sequences either leads to evolutionary change in the DNA, or it changes the gene sequence which disturbs its desirable function and affects the fitness of the organism. Mutation occurs very rarely and randomly. The physical or chemical substance which causes the mutation in the DNA is called the mutagen. Examples of the physical mutagens are radioactive substances, X-rays, and ultraviolet rays, and those of chemical mutagens are Nitrous acid, Acridine, proflavin and Base analogues.
Explanation of Solution
Chemical mutagen is the compound which causes mutation in DNA as it alters the sequence of the DNA. Types of chemical mutation:
1) Base analogue mutation
2) Intercalating agents
3) Deamination
4) Alkylating agents
1) Base analogue mutation: A base analogue is the chemical compound that mimics nitrogen bases and gets incorporated in place of normal base in the DNA. As these compounds are not the true base pair, they possess some different characters of the pairing to the complementary base pair. This wrong incorporation of the nitrogen base in the DNA leads to mutation.
A known example of the base analogue is
2) Intercalating agents: A chemical that loads itself in between the stacked bases of the DNA is called the intercalating agent. This intercalation of chemicals in DNA results in either insertion or deletion of the bases; this results in frameshift mutation of the DNA.
The examples of intercalating agents are Acridine orange, proflavin, and acriflavin. These dyes have a three ringed structure which resembles with purine- pyrimidine base pairing. Purine has a double ring structure while the pyrimidine has a single ring structure; when they pair, they form a three ring structure. When the dyes intercalate into the DNA, it results in the deletion or insertion of the of the DNA replication, therefore frameshift mutation.
A chemical mutagen causes changes in the sequence of the DNA, it is called chemical mutation.
Want to see more full solutions like this?
Chapter 11 Solutions
Genetic Analysis: An Integrated Approach (3rd Edition)
- Distinguish between spontaneous and induced mutations. Give some examples of mutagens that cause induced mutations.arrow_forwarddescribe types of mutagens with 5 examples and their mutagenic effects and mechanismsarrow_forwardplease solve the following: (a)Explain how a mutation effects a genotype. (b) Explain how a mutation may or may not effect a phenotype. (c)What is the difference between DNA replication, transcription, and translation. What are the products in each, and what are they used for? please solve accurate and exact.arrow_forward
- Exposure to various chemicals can cause DNA mutations. Classify the examples as representative of transition, transversion, or nsertion/deletion mutations. Transition replacement of T:A: with C:G treatment with nitrogen mustard causes this type of mutation oxidative deamination via nitrous acid causes this type of mutation treatment with 5-bromouracil causes the replacement of A:T with G:C Transversion replacement of G:C with T:A Answer Bank Insertion/Deletion the removal of one or more base pairs treatment with proflavin causes this type of mutationarrow_forwardIt has been noted that most transposons in humans and other organisms are located in noncoding regions of the genome regions such as introns, pseudogenes, and stretches of particular types of repetitive DNA. There are several ways to interpret this observation. Describe two possible interpretations. Which interpretation do you favor? Why?arrow_forwardDescribe three possible uses of site-directed mutagenesis.arrow_forward
- Explain the rationale behind the use of the “bag of worms” phenotype as a way to identify heterochronic mutations.arrow_forwardBriefly answer the question: Exome sequencing to identify a mutation that could cause a particular set of symptoms in a patient can reveal another genetic condition that has not yet been detected. Under what circumstances, if any, do you think patients should receive such "secondary findings"?arrow_forwardGenes with highly similar sequence are often located adjacent one another in the genome. Gene duplication commonly arises from errors in replication. When the organization of such adjacent genes is in an inverted orientation, this can reduce the expression of other genes that have similar sequence and are located on other chromosomes. Explain the mechanism of how this generally occurs. Please state the answer in details: what is the mechanism? How it happens? Why this happens? When it happens? And every other necessary information.arrow_forward
- Human Anatomy & Physiology (11th Edition)BiologyISBN:9780134580999Author:Elaine N. Marieb, Katja N. HoehnPublisher:PEARSONBiology 2eBiologyISBN:9781947172517Author:Matthew Douglas, Jung Choi, Mary Ann ClarkPublisher:OpenStaxAnatomy & PhysiologyBiologyISBN:9781259398629Author:McKinley, Michael P., O'loughlin, Valerie Dean, Bidle, Theresa StouterPublisher:Mcgraw Hill Education,
- Molecular Biology of the Cell (Sixth Edition)BiologyISBN:9780815344322Author:Bruce Alberts, Alexander D. Johnson, Julian Lewis, David Morgan, Martin Raff, Keith Roberts, Peter WalterPublisher:W. W. Norton & CompanyLaboratory Manual For Human Anatomy & PhysiologyBiologyISBN:9781260159363Author:Martin, Terry R., Prentice-craver, CynthiaPublisher:McGraw-Hill Publishing Co.Inquiry Into Life (16th Edition)BiologyISBN:9781260231700Author:Sylvia S. Mader, Michael WindelspechtPublisher:McGraw Hill Education