Sordaria Plants

Introduction

Patterns of inheritance have certain limitations, thus studying what happens to genes during meiosis is not easy. For example, in animals and plants, large numbers of primary meiocytes in males give rise to an even larger pool of reproductive cells, which only represent a small portion of the sperm or pollen. These limitations are overcome by studying fungi, which keep the product of meiosis in a membrane-bound sac known as the ascus.
Meiosis reduces the chromosome number in half during the formation of gametes in animals and spores in plants. During the first meiotic reduction division, the chromosomal pairs are partitioned so that each spore contains one of each chromosomal pair, making it haploid. When haploid spores unite during fertilization, the resulting zygote is diploid, having received one chromosome of each pair from each parent. Meiosis involves two successive nuclear divisions that produce four haploid cells. The first division (meiosis...