How Does DNA Move from Cell to Cell?

The passage of DNA from one cell to another is the basic means by which genetic information — and therefore biological characteristics — can persist relatively unchanged across millions of generations of organisms. The mechanism by which DNA is passed from one generation of cells to the next is a combination of DNA replication and cell division. In this unit, you will learn how DNA is first packaged and then passed on to the next generation during cell division. You will also explore the unpredictable ways in which DNA can change during this process.

2.1 In this unit, you will learn what happens to DNA during both mitosis, the process of cell division that happens in most cells, and meiosis, the process of cell division that happens in cells that are specifically intended to play a role in sexual reproduction. You will also discover how DNA strands can be randomly altered during either process.

2.2 Cell division, the basic means by which genetic information is passed from generation to generation, involves tightly coordinated movements of a cell's DNA. This page describes the major phases of mitosis, the most common form of cell division.

2.3 Cell division, the basic means by which genetic information is passed from generation to generation, involves tightly coordinated movements of a cell's DNA. This page describes the major phases of meiosis, a version of cell division that occurs in cells intended to play a role in sexual reproduction.

2.4 Pieces of DNA molecules are constantly being broken apart and exchanged with other DNA molecules. This process is called recombination. In this page, you will learn how recombination introduces unpredictable transformations in the information encoded in a cell's DNA.

2.5 Just like the mechanical components in cars or computers, the molecules inside a cell can sometimes malfunction. When this happens during DNA replication, the result is an unpredictable change in the nucleotide sequence of an organism's DNA. This process, called mutation, is part of what determines changes in the characteristics of populations across multiple generations.