H - C10 – Meiosis & Sexual Reproduction

Chromosomes translocation inversion can occur during

This preview shows 34 out of 41 pages.

chromosomes
Image of page 34

Subscribe to view the full document.

Translocation Inversion – Can occur during crossing over; Between non-homologous chromosomes Portion of DNA flips 180 o and reinserts The 4 alterations are usually lethal or beneficial towards survival/evolution
Image of page 35
Mutations in Chromosome Number Error occurs during Anaphase of Meiosis; Event called Nondisjunction when chromosomes do not separate properly and 1 gamete keeps 2 chromosomes the other had none. This is BAD. Disjunction is GOOD.
Image of page 36

Subscribe to view the full document.

When 1 gamete with 2 of the same chromosome # fuses with a normal gamete with 1 chromosome of the same #, it results in a zygote with 3 chromosomes of the same number instead of 2 Called Trisomy
Image of page 37
Incidence of Edward s Syndrome – Extra Chromosome # 18 • Mother s Age Rate per 1000 Births 35 0.5 39 2.0 41 3.9 43 7.6
Image of page 38

Subscribe to view the full document.

Incidence of Down Syndrome – Extra Chromosome # 21 • Mother s Age Down Syndrome Occurrence Under 30 1 : 1,500 31 – 37 1 : 290 45 + 1 : 46 WHY?
Image of page 39
Females are born with all their eggs So at age 45, their eggs are 45 years old! ! ! Males can also create trisomy gametes
Image of page 40

Subscribe to view the full document.

Disorders due to Chromosome # Down Syndrome – Turner Syndrome – Females can have – Klinefelter Syndrome – XYY – Extra #21 Female; XO; Missing a sex chromosome XXX to XXXXX Male; XXY Normal
Image of page 41
You've reached the end of this preview.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern