Which of the following cellular structures is associated with the mass of an atom?

The correct answer relates to the atomic structure, specifically focusing on the components that contribute significantly to the mass of an atom. The nucleus of an atom contains protons and neutrons, which are known as nucleons. Protons have a positive charge, while neutrons have no charge. Together, they account for nearly all of the atom's mass, making them essential for understanding atomic weight and stability.

In contrast, electrons are much lighter in mass compared to protons and neutrons and are found in orbitals surrounding the nucleus. They contribute to the atom's overall charge and chemical behavior but do not play a significant role in its mass. Membranes are biological structures and unrelated to atomic mass. Therefore, acknowledging the mass contribution from protons and neutrons is crucial for accurately identifying the cellular structure linked to atomic mass.