Final answer:
The false statement about the endomembrane system is that all its components are physically connected. While they work closely together, they are not all physically continuous, though they form a functional network for modifying, packaging, and transporting cellular substances.
Step-by-step explanation:
The false statement regarding the endomembrane system is that it is a system of interrelated membranes that are all physically connected. In fact, the different components of the endomembrane system, such as the nuclear envelope, lysosomes, vesicles, the endoplasmic reticulum (both rough and smooth), and the Golgi apparatus, as well as the plasma membrane, are functionally connected though they are not all physically continuous with one another. Components like vesicles move between these structures, carrying substances within the cell, thus ensuring an interactive and dynamic system rather than a physically interconnected network.
The endomembrane system's main functions include the synthesis, storage, and export of important molecules. It also plays a crucial role in the production and modification of lipids and proteins which are necessary for building cellular membranes and for secretion out of the cell. It is important to note that the mitochondria and chloroplasts are not part of the endomembrane system despite being involved in various aspects of cell metabolism.