The Mitochondria Mythos

Two billion years ago, a bacterium crawled inside another cell and never left.

That's the origin story of every complex cell on Earth. The invader—or maybe the guest—became the mitochondrion. It gave up its independence in exchange for protection. The host cell gave up some autonomy in exchange for power. The deal worked. It's still working, in every cell of your body, right now.

Mitochondria aren't just organelles. They're the remnants of an ancient symbiosis, still running their own DNA, still speaking a bacterial language, still negotiating with the cells they inhabit. They're also the reason you can think, move, and read this sentence—the energy that powers everything comes from these tiny bacterial engines.

This series explores the mitochondria mythos: the science of cellular power, the evidence of ancient cooperation, and why these organelles are at the center of aging, cancer, and the future of medicine.

Why Mitochondria Matter

Every second, your mitochondria produce roughly your body weight in ATP—the molecular fuel that powers every cellular process. Muscle contraction. Nerve transmission. Protein synthesis. Without mitochondria, complex life couldn't exist.

But mitochondria are more than batteries. They're:

- Decision-makers in cell death (apoptosis) - Sensors of cellular stress and nutrient status - Communicators that signal to the nucleus - Quality control systems that get recycled when damaged - Potential targets for treating aging, cancer, and metabolic disease

The more we study them, the more central they become.

The Series

Every Cell Runs on an Ancient Bacterial Engine Lynn Margulis was ridiculed for suggesting mitochondria were once free-living bacteria. She was right.

ATP: The Energy Currency of Life How mitochondria convert food into fuel through the most efficient engine evolution ever built.

Mitochondrial DNA: Your Other Genome You have two genomes. One came from both parents. One came only from your mother.

NAD+ and Aging: David Sinclair's Bet A metabolic molecule declines with age. Can replenishing it turn back the clock?

Mitophagy: Clearing Out Damaged Mitochondria Cells eat their own mitochondria to stay healthy. When this fails, disease follows.

The Warburg Effect: Cancer's Metabolic Signature Cancer cells ferment sugar even when oxygen is available. Why?

Three-Parent Babies: Mitochondrial Replacement A new technology prevents mitochondrial disease—by creating children with three genetic parents.

Synthesis: The Symbiont Within What mitochondria teach us about cooperation, identity, and the nature of complex life.

The Deep Story

Mitochondria are a window into one of evolution's most consequential experiments: the merger of two life forms into one.

That merger wasn't smooth. It took hundreds of millions of years of co-evolution. The bacterium gave up most of its genes to the host nucleus. The host cell built elaborate systems to import proteins into mitochondria, coordinate their replication, and dispose of damaged ones.

The result is a chimera—a cell that is two things at once. You are not a single organism but a collaboration. The mitochondria in your cells are the descendants of bacteria that made a deal two billion years ago. They're still honoring it.

Welcome to the power plant.