What is necessary for a cell to pass the g2 checkpoint?

For a cell to pass the G2 checkpoint, there must be accurate and complete DNA replication. There must also be a maturation promoting factor which helps to maintain the metaphase II stage arrest . The G2 also known as 2nd Gap phase, is usually responsible for continued growth and preparation for cell division. 

The answer is atmosphere. there are four spheres of the earth: 1. geosphere (from greek word 'geo' = ground), 2. hydrosphere (from greek word 'hydro' = water), 3. biosphere (from greek word 'bio' = life), and 4. atmosphere (from greek word 'atmo' = air). a magnetosphere is a region of space around astronomical objects controlled by the magnetic field of that object. through the process of elimination, since lightning is present in the air, it can be found in the atmosphere.