Nondisjunction

Draw two different ways which nondisjunction during meiosis can produce a child with Turner’s syndrome (monosomy X). You should clearly identify the X and Y chromosomes in your drawings.Drawing A                                                                     Drawing B

Prophase I Metaphase I Anaphase I Telophase I Prophase II Metaphase II Anaphase II Telophase II Haploid Daughter cells

Prophase I Metaphase I Anaphase I Telophase I Prophase II Metaphase II Anaphase II Telophase II Haploid Daughter cells

1. The X and Y chromosomes should be clearly identified in your drawings above.

2. State the sex of the person undergoing meiosis in drawing A above.

3. State the sex of the person undergoing meiosis in drawing B above.

4a. Which gamete in drawing A must fuse with a normal gamete to produce Turner’s?

4b. What is the sex chromosome make-up of the normal gamete in question 4a above?

Draw two different ways which nondisjunction during meiosis can produce a child with Klinefelter’s syndrome (XXY). You should clearly identify the X and Y chromosomes in your drawings.

Drawing A                                                                   Drawing B

Prophase I Metaphase I Anaphase I Telophase I Prophase II Metaphase II Anaphase II Telophase II Haploid Daughter cells

Prophase I Metaphase I Anaphase I Telophase I Prophase II Metaphase II Anaphase II Telophase II Haploid Daughter cells

5. The X and Y chromosomes should be clearly identified in your drawings above.

6. State the sex of the person undergoing meiosis in drawing A above.

7. State the sex of the person undergoing meiosis in drawing B above.

8a. Which gamete in drawing A must fuse with a normal gamete to produce Klinefelter’s?

8b. What is the sex chromosome make-up of the normal gamete in question 4a above?