Use the animation and your knowledge of crossing over to select the true statement.Multiple ChoiceCrossing over occurs only in males.Crossing over occurs only between genes that are heterozygous.Crossing over results in reduced genetic variation among gametes.No answer is correct.Crossing over occurs only in some chromosomes.

If crossing over occurs only between the two alleles of the same gene, as shown in the animation, what allele combinations are present in the gametes?Multiple Choiceone gamete with a parental combination of alleles, and three recombinant gametesfour gametes with parental combinations of allelesfour recombinant gametestwo gametes with parental combinations of alleles, and two recombinant gametes

Crossing over occurs between homologous chromosomes.Group of answer choicesmeiosis onlyneither mitosis nor meiosismitosis onlyboth mitosis and meiosisNext

Crossing over allows the reassortment of parental combinations of alleles.Group startsTrue or False

What is crossing over?Group of answer choicesalso referred to as the “independent assortment of chromosomes”the exchange of homologous portions of nonsister chromatidsmaking an RNA copy of a DNA stranda direct consequence of the separation of sister chromatidsthe movement of genetic material from one chromosome to a nonhomologous chromosomethe exchange of homologous portions of sister chromatidsNext

Suppose you carry out a cross with fruit flies where you follow the inheritance of alleles at four different gene loci: one locus controls body color, one locus controls eye color, one locus controls wing length, and one locus controls wing shape. At each locus, there is a dominant allele and a recessive allele. The four loci follow Mendel's principle of independent assortment. A male that is heterozygous for all four loci is crossed with a female that is also heterozygous at all four loci. Complete the sentences that predict the results of this cross using the correct terms.The probability that a male gamete will have all four recessive alleles is .The probability that the F₁ offspring will have two dominant alleles at the gene locus that controls body color is .The probability that the F₁ offspring will be homozygous at the gene locus that controls body color is .The probability that the F₁ offspring will have two dominant alleles at all four gene loci is .The probability that the F₁ offspring will have the dominant phenotype for all four traits is .