Consider the panels A-D in Figure 1. Which one panel illustrates the segregation of alleles on chromosomes in a cell of genotype M/m; B/b undergoing anaphase I of meiosis?

I am not sure how to explain what parent the nondisjunction occurred from in example 2 part 1.  Sometimes nondisjunction will occur in a parent that has normal chromosome numbers and result in an offspring that has abnormal number of chromosomes. The phenotype of the affected offspring will often allow geneticists to determine in which parent and during which division of meiosis the nondisjunction occurred. In each of the examples below, assume the parents have a normal diploid chromosome complement. EXAMPLE 1: A man with the X-linked dominant condition “brown tooth enamel” and a woman with normal tooth enamel produce a son with brown tooth enamel. Let’s call the allele for brown tooth enamel “XB” and normal tooth enamel “Xb”. In which parent did the nondisjunction occur? Explain and/or illustrate Did nondisjunction occur at meiosis I or II? Explain and/or illustrate. What sex chromosomes are in the child’s somatic cells? EXAMPLE 2: The parents in the family above produce another…

The following image shows Nondisjunction. Which of the following cells will suffer from a genetic disorder due to the occurence of Nondisjunction: Nondisjunction A DOO m+1 n+1 n-1 Number of (a) Nondisjunction of homologous chromosomes in melosis I n-1 n n+1 More than 1 of the answers Meiosis II Nondisjunction Gametes A 000 n.1 mosomes (b) Nondisjunction of si chromatics in meloe

if a species of animal has 18 chromosomes in its diploid cells (2n=18). Describe what the metaphase chromosome arrangement would look like for this species in each of the following stages: mitosis, meiosis I, and meiosis Il