Lectures

Sex Chromosomes

by Georgina Cornwall, PhD
(1)

Questions about the lecture
My Notes
  • Required.
Save Cancel
    Learning Material 2
    • PDF
      Slides 03 Chromosomal Disorders III.pdf
    • PDF
      Download Lecture Overview
    Report mistake
    Transcript
    So, I saved the best for last as far as chromosomal disorders are concerned. In this lecture, we’re going to explore disorders of the sex chromosomes, both full polyploidies, aneuploidies as well as structural disorders of the chromosomes. Sex chromosomes kind of work in a slightly different way. So, it seems fitting to put them altogether. The first question we have to consider is how do sex chromosomes actually determine the sex of an individual. It turns out it’s not quite as simple as having an X and a Y. We can have XY individuals that do not appear as a male at all. In fact, somebody has said that, one author has said that there are up to seven different sexes when you consider all the steps along the way at which sex can be determined. There are four discreet steps in the determination of the final sex of an individual. First of all, there’s the chromosomal sex determination, whether you have an X and an X, or an X and a Y. Then we have to consider gonadal sex determination, what sort of gonads is one going to have. Are they going to have ovaries or a testis or ovotestis or one of each? All of those are possibilities. Then we have the differentiation of the external genitalia. Once the gonads have developed, what then happens in order to have the genitalia, internal and external genitalia become either male or female or a mixture of both? Finally, are the development of secondary sex characteristics. Along the way, lots of different mistakes can happen. In fact, if we were to talk about brain chemistry, we could discuss the exposure to different environmental stimuli that actually impact some of the brain developments associated with these disorders also. But we’re not...

    About the Lecture

    The lecture Sex Chromosomes by Georgina Cornwall, PhD is from the course Chromosomal Disorders.


    Included Quiz Questions

    1. Maternal age at conception
    2. Chromosomes
    3. Gonads
    4. Genital differentiation
    5. Development of secondary sex characteristics
    1. At pseudoautosomal region on short arm p
    2. At pseudoautosomal region on long arm p
    3. At pseudoautosomal region on long arm q
    4. At nonhomologous region on short arm p
    5. At nonhomologous region on long arm q
    1. Week 6
    2. Week 4
    3. Week 5
    4. Week 1
    5. Week 8
    1. Phenotypic female with female genitalia
    2. Phenotypic male with female genitalia
    3. Phenotypic female with male genitalia
    4. Phenotypic male with male genitalia
    5. Phenotypic female with ambiguous genitalia
    1. Mesonephric ducts develop in response to TDF (testes determining factor)
    2. Paramesonephric ducts reduce in response to TDF (testes determining factor)
    3. Mesonephric ducts reduce in response to TDF (testes determining factor)
    4. Paramesonephric ducts develop in response to AMH (antimullerian hormone)
    5. Paramesonephric ducts develop in response to TDF (testes determining factor)
    1. Defect in chromosome 15
    2. Absence of chromosome Y
    3. Defect in SRY (sex-determining region on chromosome Y) gene
    4. Absence of TDF (testes determining factor)
    5. Absence of AMH (antimullerian hormone)

    Author of lecture Sex Chromosomes

     Georgina Cornwall, PhD

    Georgina Cornwall, PhD


    Customer reviews

    (1)
    5,0 of 5 stars
    5 Stars
    5
    4 Stars
    0
    3 Stars
    0
    2 Stars
    0
    1  Star
    0