Describe meiosis as a reduction division in which the chromosome number is halved from diploid to haploid resulting in genetically different cells (details of stages are not required)

Sourav PanNovember 3, 2024

Answered

Meiosis: A Reduction Division

Definition

Meiosis is a specialized type of cell division that occurs in sexually reproducing organisms. It results in the halving of the chromosome number from diploid (2n) to haploid (n), producing gametes such as sperm and eggs.

Key Features

1. Reduction of Chromosome Number:
   • In meiosis, a diploid parent cell, which contains two sets of chromosomes (one from each parent), undergoes two rounds of division. This process reduces the chromosome number by half:
     • Diploid (2n): The starting cell has two complete sets of chromosomes.
     • Haploid (n): The resulting gametes contain only one set of chromosomes.
2. Genetic Variation:
   • Meiosis produces genetically distinct cells due to two key processes:
     • Independent Assortment: During meiosis, the arrangement and distribution of homologous chromosomes are random, leading to various combinations of maternal and paternal chromosomes in the gametes.
     • Crossing Over: During prophase I, homologous chromosomes can exchange segments of genetic material, creating new allele combinations. This recombination contributes to genetic diversity among the resulting gametes.

Outcomes

• The end result of meiosis is four haploid cells from one diploid cell, each genetically unique. In males, these cells develop into sperm, while in females, typically one functional egg is produced along with smaller polar bodies that usually do not participate in fertilization.