The cell membrane is like the guards because they only let people that paid their flight enter. The cell membrane only let’s good things enter and not harmful things.
The cytoplasm is like the passangers filling the plane because they cytoplasm fills the cell just like the passangers fill the plane.
The chloroplast is like the solar planes because the chloroplast basically turns sun light into sugar/Glucose for the plant to get energy. The solar planes get the power of the energy of the sun to move.