Down syndrome (trisomy 21) and Edwards syn-drome (trisomy 18) are the most common autosomal triso-mies seen in human infants. Does this fact mean that thesechromosomes are the most difficult to segregate properlyduring meiosis?

Down syndrome (trisomy 21) and Edwards syn-drome (trisomy 18) are the most common autosomal triso-mies seen in human infants. Does this fact mean that thesechromosomes are the most difficult to segregate properlyduring meiosis?

Name: Down syndrome (trisomy 21) and Edwards syn-drome (trisomy 18) are the
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Description: Down syndrome (trisomy 21) and Edwards syn-drome (trisomy 18) are the most common autosomal triso-mies seen in human infants. Does this fact mean that thesechromosomes are the most difficult to segregate properlyduring meiosis?

Human Heredity: Principles and Issues (MindTap Course List)

11th Edition

ISBN:9781305251052

Author:Michael Cummings

Publisher:Michael Cummings

Chapter6: Cytogenetics: Karyotypes And Chromosome Aberrations

Section: Chapter Questions

Problem 19QP: The majority of nondisjunction events leading to Down syndrome are maternal in origin. Based on the...

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The majority of nondisjunction events leading to Down syndrome are maternal in origin. Based on the duration of meiosis in females, speculate on the possible reasons for females contributing aneuploid gametes more frequently than males do.
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Though an individual with abberations such as Robertsonian translocation may be phenotypically normal, they can generate gametes through meiosis that have atypical organizations of chromosomes, resulting in recurrent fetal abnormalities or miscarriages. Why, despite these Robertsonian translocations, are affected cells still able to generate typical gametes through meiosis?
Assume that a diploid cell (2N=8) contains 4 pairs of chromosomes (3 pairs of autosomes and 1 pair of sex chromosomes) designated as 1m, 1p, 2m, 2p, 3m, 3p, Xm, and Xp where "m" stands for maternal origin and "p" stands for paternal origin. Which of the following is/are possibilities for the chromosomal composition of each of the 2 daughter cells following meiosis 1? 1m, 2m, 3m, Xm AND 1р, 2р, Зр, Хр O 1m, 2p, 3p, Xm AND 1p, 2m, 3m, Xp O 1m, 1p, 2m, 2p, 3m, 3p, Xm, Xp AND 1m, 1p, 2m, 2p, 3m, 3p, Xm, Xp O 1m, 2p, 3m, Xp AND 1m, 2p, 3p, Xm
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