Question

what does the cell cycle have to control its progression?
checkpoints
neurological signals
phosphorylation
facilitated diffusion

Explanation:

Cell cycle progression is regulated by checkpoints. These checkpoints ensure that each stage of the cell cycle is completed accurately before moving to the next stage. For example, the G1 checkpoint checks for cell size, nutrients, growth factors, and DNA damage. If any of these are not in proper condition, the cell cycle is halted. Neurological signals are related to the nervous system and not directly involved in cell cycle control. Phosphorylation is a process (like in the activation of cyclin - dependent kinases) but it is part of the machinery that operates at checkpoints. Facilitated diffusion is a transport mechanism for molecules across the membrane and has no role in cell cycle progression control.

Answer:

checkpoints