Concept explainers
Population geneticists are interested in the
- a. a deletion of a gene sequence.
- b. a duplication of a region of a gene.
- c. a rearrangement of a gene sequence.
- d. a single-
nucleotide substitution. - e. an inversion of a segment of a chromosome.
Introduction: Polymorphism can be defined as a process by which a particular trait displays several types of variations among a population. A polymorphic population shows more than one phenotype for that particular trait.
Answer to Problem 1TY
Correct answer: A single-nucleotide substitution is the most common type of genetic change that leads to polymorphism in a population. Hence, the correct answer is option d.
Explanation of Solution
Reason for correct answer:
Single-nucleotide substitution results in the change in genetic makeup due to a change in a single nucleotide. These changes are responsible for coding different types of amino acids, which in turn will code for different proteins. Different functional protein will lead to the generation of various types of phenotypes among the members of a population. So, they are the simplest and common type of genetic change that occur in a gene.
Option d. is given as “a single-nucleotide substitution”.
The most common type of genetic change that is responsible for causing polymorphism is single-nucleotide substitution. Hence, the correct answer is option d.
Reasons for incorrect answer:
Option a. is given as, “a deletion of a gene sequence”.
A deletion in gene sequence can cause variations in the genome. However, it is not the most common type of genetic change that results in polymorphism. Hence, option a. is incorrect.
Option b. is given as, “a duplication of a region of a gene”.
Duplication of a region of gene occurs in extreme cases of genome repairing process. It also occurs due to the various types of mutation at the time of replication of genetic material. So, it is not the most common type of genetic change. Hence, option b. is incorrect.
Option c. is given as, “a rearrangement of a gene sequence”.
A rearrangement of a sequence of gene can cause polymorphism to some extent but it occurs majorly in case of genome repair. So, it is not the most common type of genetic change. Hence, option c. is incorrect.
Option e. is given as, “an inversion of a segment of a chromosome”.
Process of inversion of a segment of gene sequence is not at all related with the process of polymorphism. Hence, option e. is incorrect.
Hence, the options a., b., c., and e. are incorrect.
Single-nucleotide substitution is responsible for polymorphism. It is the most common process which results in genetic changes among the gene sequences and leads to the process of polymorphism very frequently.
Want to see more full solutions like this?
Chapter 23 Solutions
BROOKER BIOLOGY
- Please fill in the blank ———- mutations are the most common...arrow_forwardThe basic units of information that encode the proteins needed to grow and function as a living organism are called: Select one: a. Chromosomes O b. Genes c. Mutations O d. Cells O e. Mendel's postulatesarrow_forwardMost scientists consider the Human Genome Project (HGP) to be the most significant scientific project of the 21st century. Choose the statements that describe the key findings of the Human Genome Project. A. There are 23 pairs of chromosomes that make up the human genome. B. DNA exists in a double helical form. C. There are approximately three billion base pairs in the human genome. D. The human genome contains approximately 25000 genes. E. The genetic information of a cell is stored in the form of DNA.arrow_forward
- The genotype of an organism is best defined as: A. A subunit of DNA composed of a nitrogenous base, a pentose sugar, and a phosphate B. An organism’s genetic makeup; its collection of genes that determine its phenotype C. A segment of DNA that codes for a functional product D. Actual, expressed physical and biochemical properties of an organism E. A type of base substitution mutationarrow_forwardWhat happens to an organism (plant, animal, or microorganism) during genetic modification? A. Fewer desirable genes are transferred to a new species. B. Genes are removed from one organism and transferred to another. C. Plants or animals are given traits that they typically have. D. All of the abovearrow_forwardWhich of the following is not a commonly used method of modifying the DNA of an organism?a. crossbreeding two plants of the same speciesb. crossbreeding two plants of different speciesc. the polymerase chain reactiond. genetic engineeringarrow_forward
- When we compare DNA sequences among individuals, we tend to see lots or differences In non-coding regions of the genome but very few differences in coding regions, particullarly at second codon position in exons. What explains these different levels of nucleotide diversity? A. Selection on coding regions B. Selection on non-coding regions C. Different mutation rates in coding and non-coding regions D. Protien folding patterns E. all the abovearrow_forwardWhich of the following is true about DNA manipulation? Select the best answer. A. all of these B. DNA has never been transferred between different organisms. C. Transferring DNA from one organism into another always kills the host organism. D. Whole genomes have been manipulated by humans for centuries; now individual genes ca be inserted into different organisms using a variety of techniques. E. DNA can't be manipulated.arrow_forwardWhat is the scientific value of establishing a reaction norm? a. A reaction norm can assess genotype, environmental, and genotype-by-environment influences on variation. b. A reaction norm allows researchers to sample DNA from different genotypes. c. A reaction norm allows individuals to grow individuals in conditions they would never experience in nature. d. A reaction norm can assess the extent of variation between two genotypes.arrow_forward
- Many organisms are studied by geneticists. Of the following species, do you think it would be more likely for them to be studied by a transmission geneticist, a molecular geneticist, or a population geneticist? Explain your answer. Note: More than one answer may be possible. A. Dogs B E. coli C. Fruit flies D. Leopards E. Corn Lab 1arrow_forwardIn order to perform mutation on an organism, we need: 1. A mutation probability - usually a "small" value 2. A crossover point 3. The number of organisms in the population 4. Both a and barrow_forwardA researcher examines genes for several proteins that are quite similar in both structure and function. He is interested in determining whether the genes form a multigene family and in working out which of the proteins arose first evolutionarily. What would be the BEST approach to take to address this question? Be careful to look for the best approach; some other approaches could also provide useful information while being less definitive. A. The researcher should sequence the genes and compare their sequences. The most similar genes are likely the most closely related, while those that have more base differences probably diverged earlier. B. The researcher should examine the functions of the proteins. Those with the most similar functions are the most closely related. C. The researcher should induce mutations in the genes to see how these affect the function. The most mutations needed to cause changes in the function of the protein, the older the gene. D. The…arrow_forward
- Human Heredity: Principles and Issues (MindTap Co...BiologyISBN:9781305251052Author:Michael CummingsPublisher:Cengage LearningConcepts of BiologyBiologyISBN:9781938168116Author:Samantha Fowler, Rebecca Roush, James WisePublisher:OpenStax College