During oogenesis in an animal species with a haploid number of 6, one dyad undergoes nondisjunction during meiosis II. Following the second meiotic division, this dyad ends up intact in the ovum. How many chromosomes are present in (a) the mature ovum and (b) the second polar body? (c) Following fertilization by a normal sperm, what chromosome condition is created?

During oogenesis in an animal species with a haploid number of 6, one dyad undergoes nondisjunction during meiosis II. Following the second meiotic division, this dyad ends up intact in the ovum. How many chromosomes are present in (a) the mature ovum and (b) the second polar body? (c) Following fertilization by a normal sperm, what chromosome condition is created?

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 16QP: Assume that a meiotic-nondisjunction event causes trisomy 8 in a newborn. If two of the three copies...

See similar textbooks

Similar questions

Assume that a meiotic-nondisjunction event causes trisomy 8 in a newborn. If two of the three copies of chromosome 8 are absolutely identical, at what point during meiosis did the nondisjunction event take place?
Human sex chromosomes are XX for females and XY for males. a. With respect to an X-linked gene, how many different types of gametes can a male produce? b. If a female is homozygous for an X-linked allele, how many different types of gametes can she produce with respect to this allele? c. If a female is heterozygous for an X-linked allele, how many different types of gametes can she produce with respect to this allele?
A sperm cell from the fruit fly Drosophila melanogaster contains four chromosomes. How many chromosomes would be present in a spermatogonial cell about to enter meiosis? How many chromatids would be present in a spermatogo- nial cell at metaphase I of meiosis? How many would be present at metaphase II?
In the process of Oogenesis in animal cells, will the genotype of the second polar body (derived from meiosis II) always be identical to that of the ootid? Why or why not?
Male honeybees, which are haploid, produce sperm by meiosis.Explain what unusual event (compared with other animals) mustoccur during spermatogenesis in honeybees to produce sperm.Does this unusual event occur during meiosis I or meiosis II?
In kangaroos, the somatic cells are diploid, having 22 chromosomes. How many chromosomes are present in each cell at metaphase II of meiosis?
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?
If half the chromosomes of a human primary oocyte segregate into the first polar body, which degenerates, why aren’t some of the different kinds of chromosomes of the diploid chromosome complement absent from the egg
During meiosis in male mammals, sex chromosomes segregate to produce two types of sperm: X‑bearing sperm and Y‑bearing sperm. True or false?
Random orientation of homologous chromosomal pairs along the metaphase plate of the cell occurs during which phase of meiosis?
If a dog cell (2n = 78) enters meiosis, how many chromosomes will be present in each daughter cell at the end of.... -...meiosis I? -...meiosis II?
a. If cell division during gametogenesis is non-meiotic, what is its consequence to the future generations of diploid organisms? b. How does non-disjunction in meiosis lead to numerical chromosomal aberration?