Copy the following paragraph and fill in the missing blanks. Some of the words will not be used. chromatids crossing-over DNA recombination half homologous meiosis mitosis sex twice variability For eukaryotic organisms to mate through sexual reproduction, MEIOSIS occurs in their gametes or SEX cells. This process is similar to mitosis, but it has some differences such as it goes through the cell division stages twice and produces cells with HALF the number of chromosomes. The chromosomes might overlap and swap DNA fragments when they are pulled apart during Prophase I; this process is called CROSSING-OVER and it leads to more genetic VARIABILITY among the offspring

Unit 4 – Cell Cycle Definitions Due Friday (11/6/15) All Parts Due Friday (11/13/15) Period 6 – All Parts Due Thursday (11/12/15) 1.Allele 2.Anaphase 3.Cancer 4.Cell Cycle 5.Centriole 6.Centromere 7.Chromatid 8.Chromosome 9.Crossing Over 10.Cytokinesis 11.Daughter Cell 12.Diploid 13.Electrophoresis 14.Frameshift Mutation 15.Gamete 16.Gene 17.Genetic Disorder 18.Genome 19.Haploid 20.Interphase 21.Karyotype 22.Meiosis 23.Metaphase 24.Mitosis 25.Mutation 26.Offspring 27.Point Mutation 28.Prophase 29.Sexual Reproduction 30.Somatic 31.Telophase 32.Tumor Pg 54

Collect Today Page 59 – Cell Cycle Concept Map Corrections Notecard Sticker Sheet Assigned Vocabulary Quiz – TOMORROW!!! Page 61 - Mitosis vs Meiosis Notecard ALL PARTS (Friday) Cell Cycle/Vocabulary Make-Up Quiz (Friday) Most Missed Quiz Make-Up (Friday) Late Page 58 – Cell Cycle Foldable (-50%) Page 60 – Cancer Webquest (-30%)

Organize Buff Binder – Buff Binder Quiz sometime this week.

Essential Question How does meiosis differ from mitosis? Standard B.6G – Recognize the significance of meiosis in sexual reproduction Pg 61

A cell that contains both sets of homologous chromosomes is said to be diploid. Diploid means “two sets”. 2N is used to represent the number of chromosomes in a diploid cell.

The gametes contain only a single set of chromosomes and are said to be haploid. Haploid means “one set”. N is used to represent the # of chromosomes in a haploid cell.

Meiosis is a process in which the number of chromosomes per cell is cut in half through the separation of homologous chromosomes in a diploid cell. ** Meiosis is how gametes are produced**

Meiosis usually involves two divisions called meiosis 1 and meiosis 2. By the end of meiosis, the diploid cell that entered meiosis has become four haploid cells.

During Prophase I of meiosis, chromosomes line up to form homologous pairs. When crossing over occurs genetic material is exchanged between maternal and paternal chromosomes. Crossing over results in genetic variation. Label the diagram Dad’s chromosome Mom’s chromosome Crossing over Result = genetic variation

In male animals, the haploid gametes produced by meiosis are called sperm. In female animals, the haploid gametes produced by meiosis are called eggs.

Dad’s chromosome Mom’s chromosome Crossing Over DNA Replication Crossing Over MEIOSIS

Mom’s chromosome Dad’s chromosome Identical Copy MITOSIS

Mitosis results in two genetically identical diploid cells. Mitosis is used for growth and repair. Mitosis is used for somatic (body cell) production. Meiosis results in four genetically different haploid cells. Meiosis is used for gamete production and increased genetic variation.

Mitosis is used for growth and repair. Meiosis is used for gamete production and increased genetic variation.

MitosisMeiosis

Compare and Contrast Mitosis vs Meiosis by copying the diagram and filling it in.Mitosis Meiosis Mitosis MeiosisBoth