Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Cellular Reproduction Mitosis and Meiosis Cellular Reproduction • All organisms grow – From 1 billions of cells – They divide from one to two cells • Parent cell daughter cells Cells Alive Why reproduce? Asexual reproduction • New cell identical to parent – Only ONE parent – Bacteria and Amoeba • Mitosis = asexual reproduction – Asexual reproduction – budding, binary fission – Regeneration - starfish – Parthenogenesis – honey bees (new generation without fertilization Chromosomes • Made of DNA – Deoxyribo Nucleic Acid • Contain genes – Basic unit of heredity • You have 46 chromosomes in all of your cells – 2 sets of 23 • Diploid number Cell Cycle Cell cycle • Process that organizes, divides, and replicates the cell’s chromosomes • Life of the cell until it divides • I Play Music At The Club Interphase – Cell Grows – Duplicates DNA – Grows some more Mitosis 1. Prophase • Chromosomes coil • Nuclear membrane disappears • Spindle fibers form • 2. Metaphase • Chromosomes line up in the center of the cell 3. Anaphase • Chromosomes pulled apart toward the poles of the cell 4. Telophase • Cell membrane pinches to form two cells Cytokinesis – Division of the cytoplasm – 2 new cells fully formed • Identical to starting mother cell Meiosis • Process of cell division that reduces the chromosome number in half – 46 23 – How eggs and sperm are produced • Sex cells = gametes • Split into two parts – Meiosis 1 and Meiosis 2 – Similar to mitosis End result of Meiosis • 4 daughter cells • NOT identical to mother cell • Genetic diversity Comparison Mitosis & Meiosis • Mitosis – Done by somatic cells – 1 cell division – 2 daughter cells produced – Genetic info stays the same – I Play Music At The Club • Meiosis – Done by gamete producing cells – 2 cell divisions – 4 daughter cells produced – Genetic info changes – I Play Music At The Club, Play Music At The Club The “F” word • Gametes reunite in Fertilization – the chromosome number returns to the starting number – But, since any sperm can unite with any egg, who knows what you will get?! • Sexual reproduction leads to genetic diversity