Mnemonic Device:

• A Mysterious Cat Talked, Opening Organic Oranges

Explanation: to remember the Levels of Organization in multicellular organisms

• Atoms, Molecules, Cells, Tissues, Organs, Organ Systems, Organism
  • A – Atoms
  • Mysterious – Molecules
  • Cat – Cells
  • Talked – Tissues
  • Opening – Organs
  • Organic – Organ Systems
  • Oranges – Organism