My friend uses Michelin Pro Race 2 and has more punctures than me even though he's lighter. Are the GP4000 more resistant than PR2/3 ?

The Conti 4 Season is sold as a tire and tube packaged set. Why's that... do the tubes and tires work in conjunction to provide puncture resistance... do I have to use that combo? Source: http://www.wiggle.co.uk/c/Cycle/7/Tyres_-_Road_Race/