The aperture is like a pupil. You can control the aperture by setting the "Aperture Opening", also known as an F-Stop. Shutter Speed determines HOW LONG the shutter stays open.
The longer exposures ( like 1 second ) give much more light to the film than a 1/1000 of a second exposure. So even though the number may look bigger, don't be deceived! BASICALLY... they both help with lighting..how much light is brought into the camera. They also help with sharpness.
