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 (46 chromosomes) 2. Meiosis Gametes (sex cells) New daughter cells are different from each other and the original 2 divisions--> 4 haploid cells (23 chromosomes)
Introduction- Meiosis Meiosis I Chromosomes replicate (briefly quadraploid) 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 sex cells (pollen/sperm) 4 sperm produced Equal distribution of cytoplasm and organelles 2. Oogenesis Female sex cells (ova, ovules) 1 ovum and 3 polar bodies produced egg gets virtually all the cytoplasm & organelles
New input page Title: Candy Meiosis Divide into 4 panels Label panels “beginning”, “after meiosis 1”, “after meiosis 2 sperm”, “after meiosis 2 egg” As you proceed following teacher directions, draw results in each panel. Label chromosomes, organelles, diploid cell, haploid cell OUTPUT page tonight: compare/contrast spermatogenesis & oogenesis via paragraph, venn diagram or concept map
To Do and Notice Pick up a tray. Do not eat the candy until you’ve completed the activity. Use string to create a cell membrane and a nuclear envelope. Use 2 colors of gummy worm to make chromosomes that are replicated and arranged in homologous pairs. Where should they go? Spread the remaining candy around the cytoplasm. Cut the nuclear envelope into 4 pieces and set aside. Cut the cell membrane into 2 pieces and form 2 new circles. For oogenesis, uneven sizes, for spermatogenesis, equal sizes
To Do and Notice 7. Each new cell gets a replicated chromosome (gummy worm X). What has happened to the amount of genetic material in each cell? 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) go? Separate sister chromatids- one per cell. 10. Show me the final product, after you use the pieces of the original nuclear envelope to make 4 new ones and get a stamp in your notebook.
To Do and Notice OK, now you can eat the 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.