Inside a Cell

Bonus region

How does the inside a Cell work?

About 30+ trillion human cells, each with a nucleus holding DNA, mitochondria making ATP and ribosomes building proteins.

Mitochondria

Make most of the cell's ATP using oxygen. Muscle cells can have thousands.

Membrane

A double layer of fat molecules with pumps and channels — like the sodium-potassium pump — controlling what enters and leaves.

Ribosomes

Read genetic instructions to link amino acids into proteins.

Evidence & sources

• Mitochondria produce most of the chemical energy (ATP) that cells use. Evidence: established. Known: Basic cell biology. Unknown: — Source: NIH National Human Genome Research Institute, Talking Glossary: Mitochondria (Current revision).

Connected topics

• Energy Metabolism
• Potassium
• Protein
• Fat

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General education only, not medical advice. Drafted Oct 2026 · pending qualified expert review.