Final answer:
The claim that neurons often die and go into G0 phase is false. Neurons enter the G0 phase as a normal part of their functioning because they rarely divide. Neuronal death is a separate process from the cell cycle involving apoptosis or necrosis, not a cell cycle phase like G0.
Step-by-step explanation:
The statement that neurons often die and go into G0 phase is false. Neurons, which are nerve cells, typically enter the G0 phase not due to cell death, but because they are terminally differentiated and do not actively prepare to divide. The G0 phase is a quiescent stage that cells enter if they exit the cell cycle. Some cells, like lymphocytes, may temporarily enter the G0 phase and can be triggered to re-enter the cell cycle. However, neurons and mature cardiac muscle cells tend to remain in the G0 phase permanently as they do not routinely divide.
Moreover, if neurons die, they do not 'go into' G0 phase; cell death is a different process from cell cycle regulation and involves apoptosis (programmed cell death) or necrosis (uncontrolled cell death). Therefore, when neurons die, they are not in a cell cycle phase but are undergoing a process of cell removal and potential replacement by other mechanisms, often involving neural stem cells.