What role does the nucleus play in an atom?

The nucleus plays a fundamental role in the structure of the atom as it contains protons and neutrons. Protons are positively charged particles, while neutrons have no charge. The number of protons in the nucleus determines the atomic number of the element, which uniquely identifies the element itself. This means that the nucleus not only serves as the central core of the atom but also houses the key components that determine the atom's identity and what element it represents. Hence, understanding the composition and function of the nucleus is essential for grasping the basic principles of atomic structure and chemical behavior.