SUBJECT: The cell nucleus

TOPIC: Interpretation of simple data

TO THE STUDENT:

You may already know that animals and plants are made of one or more very small living units called cells. You may also know that most kinds of cells contain a still smaller part called the nucleus. A biologists wanted to know whether the nucleus of cells is necessary for life, or whether cells could live without a nucleus. He found a way to break cells into two pieces so that one piece contained the nucleus and the other piece did not. He performed this experiment on a number of different kinds of cells.

Suppose the results of this experiment were that all the cell pieces without the nuclei died. All the cell pieces that had nuclei soon re-formed into smaller but normal-looking cells, grew then to their former size, and in all other ways continued to behave exactly as do cells that have not been broken.

What interpretation would you make of this experiment and its results?