Question

mr. and mrs. smith have three sons in elementary school. two of their children are progressing normally, but their youngest son, charles, has been much slower than his siblings in developing speech and language skills. his parents are concerned that he has a learning disability and decide to investigate further. since some learning disabilities can be genetically based, their pediatrician recommends a chromosomal analysis. the results show that charles has a trisomy of the sex chromosomes, diagnosed as xyy. a mistake during sperm formation resulted in an extra copy of the y chromosome. the extra copy was passed on to charles during fertilization. most often, this chromosomal change causes no unusual physical features or medical problems, but those with trisomy of the sex chromosomes may have a higher-than-normal risk of delays in learning development. during which stage of meiosis could this mistake have occurred?

Answer 1

The chromosomal mistake leading to XYY syndrome occurred during meiosis due to nondisjunction, which is the improper separation of chromosomes or chromatids.

Step-by-step explanation:

The mistake that resulted in Charles having an extra Y chromosome, known as XYY syndrome, could have occurred during meiosis, specifically in nondisjunction during either meiosis I or meiosis II. Nondisjunction is the failure of homologous chromosomes or sister chromatids to separate properly during cell division. If this happens during the formation of sperm, an extra Y chromosome can be included in the genetic material that fertilizes the egg, leading to an individual with XYY syndrome. Charles's case of XYY syndrome tends to have a higher-than-normal risk of learning development delays, but typically does not cause unusual physical features or severe medical problems. Other disorders resulting from extra chromosomes due to nondisjunction include Down syndrome (trisomy 21), Klinefelter syndrome (XXY), and Turner syndrome (XO).

Answer 2

you answer will be ‘Anaphase ll’, if thats one of the choices