Division of Somatic & Germline Cells

Division of Somatic and Germline Cells

Introduction

In this section, we will explore the division of cells in the human body, specifically focusing on somatic and germline cells. Understanding how these cells divide is essential to grasp the fundamentals of human biology.

Somatic Cells

• Somatic cells are a crucial part of our bodies, making up virtually all the cells except those involved in reproduction.
• They undergo division primarily through a process called mitosis.

Mitosis in Somatic Cells

• Mitosis is a type of cell division that results in the formation of two identical daughter cells, each with the same number of chromosomes as the parent cell.
• It serves as a means to replace damaged or old cells and to promote growth.
• Somatic stem cells are responsible for dividing by mitosis to produce more somatic cells.

Germline Cells

• Germline cells are a distinct group of cells that give rise to gametes, which are sperm and ova (egg cells).
• They are unique because they are directly involved in reproduction.

Mitosis and Meiosis in Germline Cells

• Germline stem cells divide by both mitosis and meiosis, depending on their purpose.

Mitosis in Germline Cells

• Mitosis in germline cells helps maintain the diploid chromosome number, which means they have 23 pairs of homologous chromosomes.
• This division results in the production of more germline stem cells.

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Division of Somatic & Germline Cells

Meiosis in Germline Cells

• Meiosis is a specialised type of cell division that results in the formation of haploid gametes.
• It involves two sequential divisions.
  • The first division separates homologous chromosomes, reducing the chromosome number by half.
  • The second division separates chromatids, ensuring that each gamete contains 23 single chromosomes.

Summary

In summary, somatic cells divide primarily through mitosis, allowing for growth and tissue repair. Germline cells, on the other hand, undergo both mitosis and meiosis. Mitosis maintains the diploid chromosome number in germline stem cells, while meiosis generates haploid gametes for reproduction. Understanding these processes is fundamental to comprehending the intricacies of human biology.