Why can cells only be formed by the division of pre-existing cells?

Sourav PanNovember 7, 2024

Answered

Cells can only be formed by the division of pre-existing cells due to several fundamental biological principles that are encapsulated in the cell theory. This concept was significantly advanced by Rudolf Virchow, who stated that “Omnis cellula e cellula,” meaning “all cells arise from cells.” Here are the key reasons why this is the case:

1. Cellular Reproduction Mechanisms

• Mitosis and Meiosis: In multicellular organisms, new cells are produced through processes like mitosis and meiosis. Mitosis results in two identical daughter cells from a single parent cell, while meiosis produces gametes (sperm and egg cells) with half the genetic material. Both processes involve the replication of the cell’s DNA and subsequent division, ensuring that new cells inherit genetic information from their parent cells.
• Binary Fission in Prokaryotes: In single-celled organisms such as bacteria, reproduction occurs through binary fission, where the cell duplicates its contents and divides into two new cells. This process also emphasizes that new cells originate from pre-existing ones.

2. Genetic Continuity

• Inheritance of Genetic Material: The division processes ensure that genetic material is accurately copied and distributed to daughter cells. This continuity is crucial for maintaining the characteristics of organisms across generations. Each new cell carries a complete set of chromosomes that dictate its function and behavior.

3. Cell Theory Foundation

• Historical Context: The formulation of cell theory in the 19th century established that all living organisms are composed of cells, and these cells arise only from existing cells. This idea was revolutionary at the time, countering earlier beliefs in spontaneous generation, which suggested that life could arise from non-living matter.

4. Biological Complexity

• Complexity of Cellular Structures: Cells are complex structures containing various organelles and systems (like the cytoskeleton) that work together for cellular function. The intricate organization of these components necessitates a precise mechanism for replication and division, which is only achievable through the division of existing cells