What Are Two Pieces of Evidence to Support the Cell Theory?


Martha Robinson

The Cell Theory is a fundamental concept in biology that states that all living organisms are composed of one or more cells, and that the cell is the basic unit of life. This theory was formulated over a century ago through the work of several scientists, and today it remains one of the most widely accepted theories in biology.

There are two pieces of evidence that support the Cell Theory. The first is the observation that all living things are made up of cells. The second is the observation that cells come only from pre-existing cells.

All Living Things are Made up of Cells

One of the earliest pieces of evidence supporting the Cell Theory was provided by Robert Hooke in 1665. He used a primitive microscope to examine thin slices of cork and observed small, box-like structures which he called “cells”. Hooke’s discovery led to further investigations and eventually it was found that not only plant tissues but also animal tissues were made up of cells.

Another scientist who played an important role in supporting this theory was Matthias Schleiden. In 1838, Schleiden examined plant tissues under a microscope and concluded that each part was composed entirely of cells. Later, Theodor Schwann examined animal tissues and found they too were composed entirely of cells.

Thus, these observations clearly supported the idea that all living organisms are made up of one or more cells. Today, we know that this statement holds true for almost all living organisms on Earth.

Cells Come Only from Pre-existing Cells

The second piece of evidence supporting the Cell Theory is what we know as “cell division”. All living things reproduce by creating new individuals from existing ones. This concept applies to both multicellular organisms as well as single-celled organisms like bacteria.

Cells divide into two identical daughter cells through either Mitosis or Meiosis processes depending on their function. In both cases, two identical daughter cells are formed from a single parent cell. This process of cell division ensures that genetic material is passed down from one generation to the next.

This idea was first proposed by Rudolf Virchow in 1858, who stated that all cells arise from pre-existing cells. The theory of spontaneous generation, which suggested that life could arise spontaneously from non-living matter, was thus debunked.

In conclusion, the Cell Theory has been widely accepted for over a century due to its solid foundation in empirical evidence. The observations made by scientists like Robert Hooke, Matthias Schleiden, and Theodor Schwann have led to the understanding that all living organisms are made up of cells and cells come only from pre-existing cells. These two pieces of evidence continue to serve as the backbone of modern biology.