Candy Meiosis Objective: Use candy to make models of cell divisions of spermatogenesis & oogenesis.

Introduction- Cell division 1. Mitosis Somatic (body) cells Identical daughter cells created 1 division--> 2 diploid cells 1. Mitosis Somatic (body) cells Identical daughter cells created 1 division--> 2 diploid cells 2. Meiosis Gametes (sex cells) New daughter cells are different from each other and the original 2 divisions--> 4 haploid cells

Introduction- Meiosis Meiosis I Chromosomes replicate Homologous chromosomes pair up Crossing over can occur Chromosome number is haploid at end but chromosomes are still duplicated (X-shaped) Meiosis II Just like mitosis Sister chromatids separate

Introduction- Meiosis 1. Spermatogenesis Male gametes (pollen, sperm) 4 sperm produced Equal distribution of cytoplasm and organelles 1. Spermatogenesis Male gametes (pollen, sperm) 4 sperm produced Equal distribution of cytoplasm and organelles 2. Oogenesis Female gametes (ova, ovules) 1 ovum and 3 polar bodies produced egg gets virtually all the cytoplasm & organelles

To Do and Notice 1.Pick up a tray. Do not eat the candy until you’ve completed the activity. 2.Use string to create a cell membrane and a nuclear envelope. 3.Use 2 colors of gummy worms to make chromosomes that are replicated and arranged in homologous pairs. Where should they go? 4.Spread the remaining candy around the cytoplasm. 5.Cut the nuclear envelope into 4 pieces and set aside. 6.Cut the cell membrane into 2 pieces and form 2 new circles. 1.Pick up a tray. Do not eat the candy until you’ve completed the activity. 2.Use string to create a cell membrane and a nuclear envelope. 3.Use 2 colors of gummy worms to make chromosomes that are replicated and arranged in homologous pairs. Where should they go? 4.Spread the remaining candy around the cytoplasm. 5.Cut the nuclear envelope into 4 pieces and set aside. 6.Cut the cell membrane into 2 pieces and form 2 new circles.

To Do and Notice 7. Each new cell gets a replicated chromosome. 8. Divide the candy appropriately between the 2 cells depending upon whether you are making eggs or sperm. 9. Cut the strings again to make 4 cell membranes. Where does the candy (organelles & cytoplasm) go? Separate sister chromatids- one per cell. 10. Use the 4 pieces of string from the original nuclear envelope to make 4 new ones, show me and get a stamp in your notebook. Draw yours and another team’s with the opposite gamete. 7. Each new cell gets a replicated chromosome. 8. Divide the candy appropriately between the 2 cells depending upon whether you are making eggs or sperm. 9. Cut the strings again to make 4 cell membranes. Where does the candy (organelles & cytoplasm) go? Separate sister chromatids- one per cell. 10. Use the 4 pieces of string from the original nuclear envelope to make 4 new ones, show me and get a stamp in your notebook. Draw yours and another team’s with the opposite gamete.

To Do and Notice  OK, now you can eat the wrapped candy.  Clean up by throwing away string and extra candy pieces. Put scissors back on the trays and return them to the back of the room.  OK, now you can eat the wrapped candy.  Clean up by throwing away string and extra candy pieces. Put scissors back on the trays and return them to the back of the room.