Here's a breakdown:
* Diploid: A cell with two sets of chromosomes (one set from each parent).
* Haploid: A cell with a single set of chromosomes.
How meiosis achieves this:
1. Meiosis I:
* Homologous chromosomes pair up: Chromosomes from the same pair (one from each parent) align side-by-side.
* Crossing over: Genetic material is exchanged between homologous chromosomes, leading to genetic diversity.
* Homologous chromosomes separate: Each pair of chromosomes is pulled to opposite ends of the cell.
* Cell divides: The original cell divides into two daughter cells, each with half the number of chromosomes as the parent cell.
2. Meiosis II:
* Sister chromatids separate: The replicated chromosomes (sister chromatids) are pulled apart and separated.
* Cell divides: Each of the two daughter cells from Meiosis I divides again, resulting in four haploid daughter cells.
Key takeaway: Meiosis is essential for sexual reproduction because it ensures that each offspring inherits one chromosome from each parent, maintaining the correct number of chromosomes for the species.
