February 24

Meiosis: How Sex Cells Are Made! 🧬

📅 Lesson Overview:
In this lesson, we explored meiosis, the process by which gametes (sperm and egg cells) are formed. This process ensures that offspring inherit a unique combination of traits from their parents.

📝 What We Covered:

1️⃣ What is Meiosis?

• Meiosis is the process of creating gametes (sex cells), like sperm and egg.

• Unlike mitosis, meiosis results in cells with half the number of chromosomes (haploid).

• Why is this important? So when sperm and egg combine during fertilization, the resulting zygote has the correct diploid number of chromosomes.

2️⃣ How Does Meiosis Work?

• Two Rounds of Division:

  • Meiosis I – Homologous chromosomes separate.

  • Meiosis II – Sister chromatids separate, creating four unique haploid cells.

• This ensures genetic variation, which is why siblings don’t look identical!

3️⃣ Comparing Mitosis vs. Meiosis

• Mitosis produces two identical daughter cells (for growth & repair).

• Meiosis produces four genetically different cells (for reproduction).

• Gametes (sperm & egg) are haploid (23 chromosomes), while all other cells are diploid (46 chromosomes).

4️⃣ Practice Problems

• Determined chromosome numbers in different organisms.

• Example: If a coyote has 39 chromosomes in a sperm cell, how many are in its skin cell? (78!)

💡 Why This Matters:

Meiosis is why you are genetically unique! It explains heredity, genetic diversity, and inherited traits. Understanding meiosis helps in fields like medicine, genetics, and evolutionary biology.

✅ Great job working through meiosis today! Keep reviewing the steps to prepare for upcoming activities. 🧬✨