Here's why:

* Atomic Number: Uranium has an atomic number of 92, meaning it has 92 protons and 92 electrons.

* Electron Configuration: The electron configuration of Uranium is:

* 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹⁴ 5d¹⁰ 6p⁶ 7s² 5f³ 6d¹

* Electron Shells: Each number in the configuration (1, 2, 3, 4, 5, 6, 7) represents a different electron shell.

Therefore, uranium has 7 electron shells.