Video Transcript
Virchow is credited with several key discoveries. Which of the following discoveries was related to cell theory? (A) The definition of the cell as the basic unit of a plant’s structure. (B) All living cells can only arise by cell division from preexisting cells. (C) All diseases involve changes in normal cells. (D) None of the answers are correct.
This question asks us about a scientist who lived in the 1850s named Rudolph
Virchow. His discoveries contributed to our understanding of cell theory, which is composed of
three principles. The first is that all living things are made of at least one cell. The second is that these cells are the basic unit of life. And the third principle of cell theory is that all cells come from preexisting
cells. Let’s review some of the scientists who contributed to cell theory in order to answer
our question correctly.
The discoveries related to cell theory were only made possible after microscopes were
first made in the late 1500s. This is because cells are microscopic, which means they can only be viewed under
magnification. The first scientist to coin the word “cell” was Robert Hooke, who lived in the
1600s. He named these after observing cork under the microscope.
In the 1800s, Matthias Schleiden proposed that all plants are composed of cells and
Theodore Schwann proposed that all animals are made of cells. These ideas contributed to the idea that all living things are composed of cells,
which are the basic unit of life. Also in the 1800s, Rudolph Virchow proposed that all cells arise from preexisting
cells, which challenged the popular understanding of the time known as spontaneous
generation. This discovery by Rudolph Virchow was very important for creating a foundation to
study diseases at the cellular level.
After reviewing different discoveries that led to cell theory, we should be able to
answer our question correctly. Our question asks about Rudolph Virchow, who we just learned was a scientist who
proposed that all cells come from other cells. This is indicated by answer choice (B). All living cells can only arise by cell division from preexisting cells.
