What’s Buggin’ You? Mosquito Meiosis Name: _______________________ Date: ________________________ Pd. _______ Background: Both mitosis and meiosis are nuclear processes that occur during cell division. Mitosis takes place in tissue that are not responsible for gametes (sperm and ova). Meiosis takes place in the testes and ovaries and results in the production of gametes. Organisms that reproduce through sexual reproduction get half their chromosomes from their father’s gamete (sperm) and half from their mother’s gamete (ova). Cells that have the full set of chromosomes are called DIPLOID or 2n. Cells which have half the normal number of chromosomes are called HAPLOID or n. In mitosis, the parent cell divides to form two identical diploid daughter cells. Each daughter cell will have the same number of chromosomes as the parent cell. In meiosis, the parent cell undergoes a series of two cell divisions which will result in four haploid daughter cells. Each daughter cell is unique and has half the number of chromosomes of the original parent cell. In this model, you will be using mosquito chromosomes. The diploid body cell of a mosquito contains 6 chromosomes. You will be modeling mosquito mitosis and meiosis. Part 1: Modeling MITOSIS Use the column of chromosomes on the back labeled for mitosis. Color the homologous chromosomes. One color will represent the chromosomes of the mother and the other color represents the chromosomes of the father. Remember, these chromosomes need to be colored at random. Using a large piece of paper, draw one large circle to represent the cell. Place your chromosomes as they would be in metaphase of mitosis. Show this to your teacher to receive a stamp below: How many chromosomes at this point? ____________ How many copies of each chromosomes at this point? _____________ Is the cell haploid or diploid? _____________________ Cut your chromosomes apart as they would be separated during anaphase of mitosis. Draw two smaller circles on your large paper to represent the two daughter cells. Place your chromosomes in the daughter cells. Show the daughter cells to your teacher to receive a stamp below: Mother’s color: _____________________ Father’s color: _____________________

Part 2: Modeling MEIOSIS Use the columns of chromosomes on the back labeled for meiosis. Color the homologous chromosomes. One color will represent the chromosomes of the mother and the other color represents the chromosomes of the father. Remember, these chromosomes need to be colored at random. Using a large piece of paper, draw one large circle to represent the cell. Place your chromosomes as they would be in metaphase I of meiosis. Show this to your teacher to receive a stamp below: How many chromosomes at this point? ____________ How many copies of each chromosomes at this point? _____________ Is the cell haploid or diploid? _____________________ Cut your chromosomes apart as they would be separated during anaphase I of meiosis. Draw two smaller circles on your large paper to represent the two daughter cells. Place your chromosomes in the daughter cells as they would appear in metaphase II. Show the daughter cells to your teacher to receive a stamp below: Cut your chromosomes apart as they would be separated during anaphase II of meiosis. Draw four smaller circles on your large paper to represent the four daughter cells. Place your chromosomes in the daughter cells. Show the daughter cells to your teacher to receive a stamp below: Analysis Questions _____ 6. During metaphase I, the chromosomes are aligned: a) Single file b) Double file _____ 7. During which phase of Meiosis do the homologous chromosomes separate from each other? a) Metaphase I b) Anaphase I c) Metaphase II d) Anaphase II _____ 8. During which phase of Meiosis do the sister chromatids separate from each other? 9. During which phase of Meiosis do tetrads form?__________________________ 10. If diploid cells in a porcupine have 34 chromosomes, how many chromosomes will the gametes have? __________ Mother’s color: _____________________ Father’s color: _____________________

Chromosomes for MITOSIS 1 Chromosomes for MEIOSIS 1 A 2 3 3 C A 2 B C B

Chromosomes for MITOSIS 2 Chromosomes for MEIOSIS C 2 B 1 3 C 1 A 3 A B

Chromosomes for MITOSIS Chromosomes for MEIOSIS B C 3 C 2 A 2 B 1 A 3 1