Concept explainers
Production of more than one
- a. pleiotrofy.
- b. genetic determinism.
- c. codominance.
- d. penetrance.
- e. genetic recombination
Introduction:
A single gene is responsible for the production of multiple phenotypes and this is termed as a pleiotropic effect. The gene influences multiple traits of organisms, which may transfer from one generation to another. In humans, phenylketonuria (PKU) is associated with pleiotropy. Phenylalanine hydroxylase converts phenylalanine to tyrosine; the mutation in phenylalanine hydroxylase encoding genes leads to multiple traits associated with phenylketonuria. It causes mental disorders, pigment defects, and eczema.
Answer to Problem 1TYR
Correct answer:
A single gene influences multiple or more than a phenotypic trait and is known as pleiotropy. Therefore, option a is correct.
Explanation of Solution
Justify reasons for the correct statement:
A single gene produces numerous phenotypic traits and is called as pleiotropy.
Option (a) is given as “pleiotropy”.
Multiple phenotypic characters produced by a gene is known as pleiotropy.
Hence, option (a) is correct.
Justify reasons for the incorrect statements:
Option (b) is given as “genetic determinism”.
Controlling of race, sex, and mental health by genes is known as genetic determinism. Hence, it is a wrong answer.
Option (c) is given as “codominance”.
Expression of both alleles of a gene in an organism is known as codominance. Hence, it is a wrong answer.
Option (d) is given as “penetrance”.
Exhibition of expected phenotype from the percentage of the given genotype is known as penetrance. Hence, it is a wrong answer.
Option (e) is given as “genetic recombination”.
Exchange of genetic material between two chromosomes or a different location of a single chromosome is known as genetic recombination. Hence, it is a wrong answer.
Hence, options (b), (c), (d), and (e) are incorrect.
A single gene produces numerous phenotypic traits and is called as pleiotropy.
Want to see more full solutions like this?
Chapter 4 Solutions
Anatomy & Physiology: The Unity of Form and Function
Additional Science Textbook Solutions
Chemistry: A Molecular Approach (4th Edition)
Microbiology Fundamentals: A Clinical Approach
Human Physiology: An Integrated Approach (8th Edition)
Campbell Essential Biology (7th Edition)
- A researcher crosses mice with brown eyes and long tails, and the F1 progeny were recovered in the following numbers and phenotypic classes: F1: 6 apricot, short : 30 brown, long : 15 brown, short : 9 apricot, long You know the genes encoding these traits are autosomal, completely dominant and assort independently. You want to use a chi-square test to analyse these results. a) Making use of the appropriate genetic convention for naming alleles, give the genotype of the male parent in this cross. b) What is your null hypothesis for the chi-square test? c) Give the expected number of individuals in the "brown, long" class. d) You obtain a value of 3.47 for the chi-square test. What conclusion can you make from the results of the chi-square test? P df 0.995 0.975 0.9 0.5 0.1 0.05* 0.025 0.01 0.005 1 0.000 0.000 0.016 0.455 2.706 3.841 5.024 6.635 7.879 2 0.010 0.051 0.211 1.386 4.605 5.991 7.378 9.210 10.597 0.072 0.216 0.584 2.366 6.251 7.815 9.348 11.345 12.838 4 0.207 0.484 1.064 3.357…arrow_forwardIndicate which of the four major classes of rearrangements (deletions, duplications, inversions, and translocations) are most likely to be associated with each of thefollowing phenomena. In each case, explain the effect.a. semisterilityb. lethalityc. vulnerability to mutationd. altered genetic mape. haploinsufficiencyf. neomorphic mutationg. hypermorphic mutationh. crossover suppressioni. aneuploidyarrow_forwardWhat can you assert regarding cytoplasmic inherited traits? A. extensive phenotypic variation exhibited, even within a single family B. reciprocal crosses that give different results C. All of the answers are correct. D. usually inherited from one parent, typically the maternal parent E. present in both males and femalesarrow_forward
- In the diagram in the box below the horizontal line represents a chromosome and A, B, C, D and E represent the position of genes on the chromosome. You would expect the highest frequency of recombination of genes to occur between? A BC D E Lll S a) Between genes B and D b) Between genes B and C c) Between genes A and B d) Between genes A and Carrow_forwardWhich of the following best describes the concept of independent assortment? Group of answer choices a. 2n, where n = number of chromosomes b. Gametes receive one of each chromosome pair but which chromosome it receives is decided randomly c. Refers to the Mendelian genetics d. Independent assortment always occurs at prophase 2 in eukaryotic organisms. e. Is the process of specified segregation and assortment of chromosomes in an organism.arrow_forwardExamination of a karyotype reveals 23 pairs of chromosomes, with each homologous pair illustrating similar size and centromere location. Which of the following can be concluded from this karyotype?a. The individual has Down syndrome.b. The individual is a female.c. The individual does not have cystic fibrosis.d. The individual does not have sickle-cell anemia.arrow_forward
- As a biologist, you complete a test cross between fly offspring to gain information about how two genes interact. You find that 20% of these test cross offspring are parental types and 80% are recombinant types. Which of the following is true based on these results? a. The alleles of the genes in question did not go through independent assortment b. The genes in question are likely located on different chromosomes c. There is a 100% frequency of recombination in this test cross d. Most of the test cross offspring look like their parentsarrow_forwardHow would one explain a testcross involving F1 dihybrid flies in which more parental-type offspring than recombinant-type offspring are produced? Group of answer choices A. The testcross was improperly performed B. The two genes are linked C. Both of the characters are controlled by more than one gene D. The two genes are linked but on different chromosomes E. Recombination did not occur in the cell during meiosisarrow_forwardCreate a chromosome map for each set of three genes from the given information. b) the crossover frequency between gene X and gene Z is 8.5 %, the crossover frequency between gene Y and gene Z is 2.25 % and between gene Y and gene X is 6.25 %arrow_forward
- When recombination (“crossing over”) doesn’t happen correctly, what type(s) of mutations that can occur? circle all that apply Select one or more: a. Inversion (reversal or “flipping” of part of a chromosome) b. Duplication of part of a chromosome c. Translocation (transfer of part of a chromosome to a non-homologous chromosome) d. Deletion of part of a chromosomearrow_forwardBecause of recombination: a. new alleles are created. b. haplotypes shorten with each generation. c. genetic diversity is decreased. d. female and male phenotypes differ. e. None of the above is correctarrow_forwardIndicate which of the four major classes of rearrangements (deletion, duplication, inversions, and translocations) are most likely to be associated with each of the following phenomena. In each case, explain the effect. a. Semisterility b. Lethality c. Vulnerability to mutation d. Haploinsufficiency e. Hypermorphic mutation (a gain of function mutation that causes an increase in otherwise normal gene function) f. Crossover suppression g. Aneuploidyarrow_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