What components are involved in the pressurization system of a 737-800?

The pressurization system of a 737-800 involves various components, and the inclusion of bleed compressors and pressure controllers is fundamental to its operation. Bleed compressors play a critical role by extracting compressed air from the engines or auxiliary power unit (APU), which is necessary for creating the pressurized environment in the cabin during flight. This compressed air is vital for maintaining a safe and comfortable atmosphere for passengers and crew at high altitudes.

Pressure controllers are responsible for monitoring and adjusting the cabin pressure based on changes in altitude, ensuring that the cabin remains at a comfortable pressure level regardless of the external atmospheric conditions. Together, these components work in harmony to effectively manage cabin pressurization, providing safety and comfort throughout the flight.

The other choices do not encompass the complete system necessary for cabin pressurization. For instance, simply having bleed compressors does not account for the need for pressure regulation, which is crucial for safe operation. Additionally, pressure controllers are distinct from components such as fuel pumps or humidity systems, which serve different functions within the aircraft.