Explain how recombination increases the amount of genetic variation in offspring: Explain why
it is not possible to have a recombination frequency of greater than 50% (half recombinant
progeny): A second pair of Drosophila are mated. The female is Cucu YY (straight wing, gray
body), while the male is Cucu yy (straight wing, yellow body). Assuming recombination,
perform the cross and list the offspring genotypes and phenotypes.
Solution
Que-3:
The recombination frequency is the measure of genetic linkage at different loci. The value of
recombination frequency is 50% if the chromosomal genes are located at different regions on the
different chromosome because of independent assortment. If the genes are located closely
together on the same chromosome, then those genes considered as genetically linked; because
they have not assorted independently due to \"crossing over\", then the recombination frequency
value is less than 50%. Linked genes are due to linkage often do not obey Mendel\'s laws of
inheritance such as independent assortment because of \"crossing over with reciprocal exchange
of hereditary genetic material meticulously in between non-sister chromatids\" at the time of
\"synapsis formation\" (propahse -I) in reduction division or meiosis 1. These events are leading
to formation of gamete cells with complete different genotypically from diploid parent
reproductive cell via meiosis finally induce \"genetic variation\" in phenotype due to
\"fertilization\" events between sperm cells & ovum.
The recombination of chromosomes enables meiosis process of cell division with the generation
of novel recombinant nucleotide -sequences by crossing over during the cell division in both
unicellular and multicellular species. Sometimes, double strand breaks in DNA during
homologous chromosomal recombination may be produced due to exposure any harmful
radiation finally may cause higher genetic variation via duplication followed by fertilization to
form a phenotype with higher genetic variation
Que-4:
Crossing over is somewhat randomly distributed over the length of the chromosome because if
the two genes are close together then it is very change to get exchange of chromosomal breaks
therefore, if the two genes are located farther apart then there will be higher room for the
exchange of genetic material with chromosomal breaks. Therefore, when two genetic are far
apart on the same chromosome are more likely to have a crossover between them than two loci
that are close together. This recombination frequency is considered as a measure of genetic
linkage during the crossover of the homologous chromosomes. Linkage disequilibrium defined
as the existence of alleles at different loci with the absence of genetic linkage between them even
though there is no equilibrium with allelic frequencies independently. The recombination
frequency is the measure of genetic linkage at different loci. The value of recombination
frequency is 50% \"if the chromosomal genes are .
Explain how recombination increases the amount of genetic variation i.pdf
1. Explain how recombination increases the amount of genetic variation in offspring: Explain why
it is not possible to have a recombination frequency of greater than 50% (half recombinant
progeny): A second pair of Drosophila are mated. The female is Cucu YY (straight wing, gray
body), while the male is Cucu yy (straight wing, yellow body). Assuming recombination,
perform the cross and list the offspring genotypes and phenotypes.
Solution
Que-3:
The recombination frequency is the measure of genetic linkage at different loci. The value of
recombination frequency is 50% if the chromosomal genes are located at different regions on the
different chromosome because of independent assortment. If the genes are located closely
together on the same chromosome, then those genes considered as genetically linked; because
they have not assorted independently due to "crossing over", then the recombination frequency
value is less than 50%. Linked genes are due to linkage often do not obey Mendel's laws of
inheritance such as independent assortment because of "crossing over with reciprocal exchange
of hereditary genetic material meticulously in between non-sister chromatids" at the time of
"synapsis formation" (propahse -I) in reduction division or meiosis 1. These events are leading
to formation of gamete cells with complete different genotypically from diploid parent
reproductive cell via meiosis finally induce "genetic variation" in phenotype due to
"fertilization" events between sperm cells & ovum.
The recombination of chromosomes enables meiosis process of cell division with the generation
of novel recombinant nucleotide -sequences by crossing over during the cell division in both
unicellular and multicellular species. Sometimes, double strand breaks in DNA during
homologous chromosomal recombination may be produced due to exposure any harmful
radiation finally may cause higher genetic variation via duplication followed by fertilization to
form a phenotype with higher genetic variation
Que-4:
Crossing over is somewhat randomly distributed over the length of the chromosome because if
the two genes are close together then it is very change to get exchange of chromosomal breaks
therefore, if the two genes are located farther apart then there will be higher room for the
exchange of genetic material with chromosomal breaks. Therefore, when two genetic are far
apart on the same chromosome are more likely to have a crossover between them than two loci
that are close together. This recombination frequency is considered as a measure of genetic
linkage during the crossover of the homologous chromosomes. Linkage disequilibrium defined
as the existence of alleles at different loci with the absence of genetic linkage between them even
2. though there is no equilibrium with allelic frequencies independently. The recombination
frequency is the measure of genetic linkage at different loci. The value of recombination
frequency is 50% "if the chromosomal genes are located at different regions on the different
chromosome because of independent assortment" therefore frequency is not possibel to have
>50%. If the genes are located closely together on the same chromosome, then those genes
considered as genetically linked; because they have not assorted independently, then the
recombination frequency value is less than 50% or 50 map units.
