Concept explainers
To review: The fact that “inversions and reciprocal translocations are less lethal than aneuploidy, duplication, deletions and nonreciprocal translocation”.
Concept introduction: The aberration in chromosome structure and function can be caused due to aneuploidy, duplication, deletions and translocations. These can alter the chromosome to cause genetic disorders. Aneuploidy is a type of chromosomal alteration in which the number of chromosome changes. Duplication refers to the repetition of a segment on the chromosome. Deletion is the removal of a segment of a chromosome and the translocation is the transfer of a segment from one locus to another locus on the chromosome. Inversion is the insertion of a segment of chromosome in reverse order.
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- Why are the X and Y chromosomes not considered homologous even though they recombine at the PAR region?arrow_forwardChromosome structural errors can occur during Meiosis which can lead to health disorders. Examine the figure below and select the correct order of error type from left to right in which they appear. duplicati on, translocation, deleti on, inversion duplication, inversion, del etion, translocation O deletion, translocati on, inversion, duplication O translocation, inversion, duplication, deletion inversion, translocation, duplication, deletionarrow_forwardInversions are known to affect crossing-over. The following homologs have the indicated order (the filled and open circles indicate centromeres): • (A B C D E) o (A D C B E) b. Diagram the alignment of these chromosomes during meiosis.arrow_forward
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