Final answer:
Importin 1 and Exportin 1 are not the same; Importin 1 is involved in importing proteins into the nucleus, while Exportin 1 is involved in exporting proteins out of the nucleus.
Step-by-step explanation:
The statement that Importin 1 and Exportin 1 are the same protein and their function is determined by whether the cargo has a Nuclear Localization Signal (NLS) or Nuclear Export Signal (NES) is False. Importin 1 and Exportin 1 are distinct proteins that perform different functions within the cell. Importin 1 recognizes and binds to the NLS on proteins destined for the nucleus, helping them to enter the nuclear pore complex. Conversely, Exportin 1 recognizes and binds to the NES on proteins and participates in their export from the nucleus. Nuclear transport receptors, such as Importin 1 and Exportin 1, are key components of the nuclear transport system, ensuring that proteins reach their correct cellular destinations.