Here's why:

* Mitochondria have their own DNA: Mitochondria, often called the "powerhouses of the cell," have their own small, circular DNA molecule separate from the DNA in the cell nucleus.

* Sperm contribute little mitochondria: During fertilization, the sperm contributes only its nucleus (containing nuclear DNA) to the egg. The sperm's mitochondria are usually discarded.

* Eggs are packed with mitochondria: The egg cell is packed with mitochondria, which are essential for the early stages of development.

Therefore, the vast majority of mitochondria in your cells come from the maternal lineage.

However, it's important to note:

* There are exceptions: Some cases, like rare mutations, can lead to a small amount of paternal mitochondrial DNA being incorporated.

* The "mitochondrial Eve": The concept of a "mitochondrial Eve" refers to the common ancestor from whom everyone alive today inherited their mitochondrial DNA. It's not a specific individual, but rather a theoretical ancestor representing the shared lineage.

So while it's generally accurate to say that almost all your mitochondria come from your mother, there are occasional exceptions and the story of mitochondrial inheritance is complex and fascinating!