Name: _________________________________________________ Date: _______________ Period: ________ Biology Notes: Meiosis Directions: Fill in the blanks as we cover the topic in the PowerPoint. What is Meiosis? •
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Defined: Process where the __________________ number is ________________ by ______________. ___________________ created (egg & sperm) End Result: ____________ _____________ Cells Interphase: ____________ process that we’ve learned before. •
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G1: _________________ S: ____________________ duplicated G2: ___________________ Prophase I: _____________________ as mitosis, except… Two Events: 1. ______________________: Pairing of _____________________________ chromosomes •
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Dad’s #1 chromosome pairs with Mom’s #1, etc… The___________________ paired chromatids equals a ____________________. 2. ______________________: Exchange of genes *Important for sexual reproduction & variation Metaphase I: •
_______________________ chromosomes (___________) align along cell __________________ Anaphase I: • Tetrads ____________________ • ______________________ chromosomes are pulled to _________________ ends Telophase I: • Cytokinesis __________________ the cells (cytoplasm) • Each ___________ contains _______ of the __________________ chromosomes Prophase II: •
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________________________ as mitosis Note:_______ __________ DNA was created (no 2nd interphase) Metaphse II: • _________________________ chromosomes are aligned at cell ____________________ Anaphase II: • Sister _______________________are pulled to opposite ends Telophase II: • _________________ divides the cells • Nucleus ___________________on the four new cells • _____________________ uncoil • End Result: _____________ ___________________ cells What is Spermatogenesis? •
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Defined: Production of ________________cells Location: male ________________ Makes final ________________ to sperm cell ______________ haploid sperm ____________at a time What is Oogenesis? • Defined: Production of the ____________ cell (____________) • In female ____________________ • During meiosis I: __________________ distributed _______________________ After meiosis II: • ___________cell matures • 3 “__________________________”dissolve • Division of gametes
• Ex: Sperm and Egg
cells
• End Result: 4
Haploid cells
• Importance:
Reduces the gamete
chromosome number
by half
• Division of somatic
cells
• Ex: Blood cells, skin
cells, nerve cells…
• End Result: 2 Diploid
Cells
• Importance: Replaces
aging cells
• Importance: Form of
asexual reproduction
Review 1)Name three ways that meiosis and mitosis differ. 2) Pick a stage of meiosis…any stage. Describe what happens in it. 3) What type of cells does meiosis create? 4) What are homologous chromosomes? 5) When do homologous chromosomes move to opposite ends of the cell? 6) When do chromatids move to opposite ends of the cell? 7) Why is no DNA created in meiosis 2? 8) How does meiosis differ in males vs. females?