Bio quiz

1. Explain how the stages of the cell cycle are necessary to start meiosis

   1. The cell needs to grow during G1 phase 

   2. so it can copy all the chromosomes in S phase

   3. Then in G2 phase they get ready for meiosis

   4. They ensure the cell is ready for DNA replication and division

2. Explain stages of meiosis and how they lead to four unique haploid cells:

   1. Prophase I

      • Important phase of crossing over 

   2. Metaphase I

      • Homologous chromosomes line up in center

   3. Anaphase I

      • Homologous chromosomes separate

   4. Telophase I

      • Split

   5. Interkinesis

      •  (waiting phase without DNA replication)  

      • (cell is now haploid with 2X DNA)

   6. Prophase II

   7. Metaphase II

      • Duplicated chromosomes line up at center

   8. Anaphase II

      • sister chromatids separate

   9. Telophase II

   10. Cytokinesis

3. Explain how this process leads to variation in gametes and why this is important for a species. .

1. The process of crossing over and independent assortment make a variation in gametes by recombining and shuffling genetic material. This leads to a unique combination of chromosomes and genes in each gamete. 

2. This is important for a species because it creates diversity and allows populations to adapt and evolve. 

4. Describe crossing over and explain how this leads to more variation in gametes 

   1. Chromosomes may break and exchange segments

   2. This process makes chromosomes with different dominant and recessive alleles- allowing for more variation

      • Crossing over occurs during prophase I

5. Students will create a model that shows the life cycle of humans and explains where and when mitosis, meiosis, and fertilization occurs. This model will include the terms diploid and haploid. 

   1. After anaphase 1 you become a haploid

1. Meiosis

2. Fertilization

3. Mitosis