Review of Gamete Formation (Nursing)

00:01 Welcome! In this lecture we will be discussing the physiology of the female reproductive system.

00:10 So before we talk specifically about the female reproductive physiology, recall that gamete formation in the female reproductive system is going to involve the formation of haploid cells.

00:25 So in our body, most of our body cells or somatic cells have 46 chromosomes.

00:33 We have two sets of 23 pairs of chromosomes.

00:37 Where one is the maternal chromosome and the other is the paternal chromosome.

00:43 Together we call this pair of homologous pairs or homologous chromosomes.

00:50 46 is referred to as are diploid chromosomal number and sometimes is going to be annotated as 2N.

01:01 In our gametes cells we only have 23 or half the number of chromosomes.

01:07 This is are haploid chromosome number or n.

01:12 This is because only one member of the homologous pairs are going to find themselves in these gametes cells.

01:20 So formation of these haploid cells requires a process known as meiosis.

01:27 Let's do a quick recap of mitosis and meiosis.

01:31 So in mitosis, we're going to start with our 46 chromosomes and which all 46 will line up along the midline of the cell during metaphase.

01:43 At the end of mitosis, we will end up with two daughter cells that are diploid and genetically identical to the mother cell.

01:53 In meiosis, however, we're going to have two cell divisions.

01:58 In the first cell division, we're going to separate the homologous pairs from each other and in the second cell division, we're going to separate the sister chromatids.

02:10 At the end of meiosis, we end up with four daughter cells that each contain one of those chromosomes in the homologous pair.