12 Sexual Reproduction and Genetic VariationGenetic variation describes the genetic differences in DNA segments of organisms within a population. Genetic variationis important because it enables some individuals to have traits that are favorable in a changing environment. Sexualreproduction is a method that introduces genetic variation.A human being is a diploid organism whose somatic cells contain 46 chromosomes found in 23 homologous pairs. Sexualreproduction requires that sex cells, or gametes, reduce their number of chromosomes in order for fertilization to occur.In humans, meiosis is the process that forms the gametes required for reproduction. The diagram shows the process ofmeiosis.CytokinesisInterphaseG¹Crossing overTelophaseIIAnaphase||InterphaseSProphaseMetaphase24Metaphase ProphaseTelophaseAnaphaseIGenetic variation can be introduced during the process of meiosis in different ways as shown in the table.The exchange of genetic material between non-sisterchromatids of homologous chromosomes.As the chromosome pairs line up during prophase I, some material from the chromatids switch to the exactsame position on the other chromosomes. This exchange can happen multiple times on the same pair ofchromosomes. The diagram shows crossing over and the resulting gametes.11HomologousPairOOA.Which BEST describes how crossing over increases genetic diversity?B.C·|-||||Bb BOO DBCrossingoverGametesCrossing over increases genetic diversity because it prevents genetic mutations from occurring withinthe genes.Crossing over increases genetic diversity because it ensures that offspring receive the dominantalleles for traits.Crossing over increases genetic diversity because it results in new combinations of genes on eachchromosome.Crossing over increases genetic diversity because it creates an uneven amount of genetic material onthe chromatids. CytokinesisCrossing overLaw ofsegregationLaw ofIndependentassortmentRandomfertilizationTelophaseMutationAAnaphaseII(818)Genetic variation can be introduced during the process of meiosis in different ways as shown in the table.The exchange of genetic material between non-sisterchromatids of homologous chromosomes.MetaphaseMetaphase ProphaseTelophaseAlleles that are normally paired are separated, andeach gamete receives only one randomly selectedcopy of a gene.The alleles of different genes do not influence oneanother and get sorted Into gametes Independentlyof one another.AnaphaseIFertilization is a random event where any malegamete can fuse with any female gamete to forma new individual.Gametes receive too few or too many chromosomes.cnrACIBHorWhOOOO

Crossing over is a key cellular event that occurs during the meiosis I of cell division. During this…

Sexual Reproduction and Genetic Variation Genetic variation describes the genetic differences in DNA segments of organisms within a population. Genetic variation is important because it enables some individuals to have traits that are favorable in a changing environment. Sexual reproduction is a method that introduces genetic variation. A human being is a diploid organism whose somatic cells contain 46 chromosomes found in 23 homologous pairs. Sexual reproduction requires that sex cells, or gametes, reduce their number of chromosomes in order for fertilization to occur. In humans, meiosis is the process that forms the gametes required for reproduction. The diagram shows the process of meiosis. Cytokinesis Interphase G' Telophase 11 Anaphase II Interphase Prophase Metaphase Metaphase Prophase Crossing over chromatids of homologous chromosomes. Telophase Anaphase I 7 Genetic variation can be introduced during the process of meiosis in different ways as shown in the table. The exchange of genetic material between non-sister As the chromosome pairs line up during prophase I, some material from the chromatids switch to the exact same position on the other chromosomes. This exchange can happen multiple times on the same pair of chromosomes. The diagram shows crossing over and the resulting gametes. CA 0₂ M-1111 Homologous Pair Crossing over Which BEST describes how crossing over increases genetic diversity? C D O O A Crossing over increases genetic diversity because it prevents genetic mutations from occurring within the genes. B B D. Gametes Crossing over increases genetic diversity because it ensures that offspring receive the dominant alleles for traits. Crossing over increases genetic diversity because it results in new combinations of genes on each chromosome. Crossing over increases genetic diversity because it creates an uneven amount of genetic material on the chromatids.

4th Edition

ISBN:9781305389892

Author:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Publisher:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Chapter11: Meiosis: The Cellular Basis Of Sexual Reproduction

Section: Chapter Questions

Problem 1ITD