This is an important point, because physicists such as Lee Smolin argue that the notion of unification requires the different kinds of elementary particle to be merely different states of a single underlying elementary entity, and argue that string theory permits this, where the notion of a point particle doesn't: "If the elementary particle was something of a certain size, there would be no difficulty imagining it to exist in different states. It might be, for example, that the particle could take on different shapes. But it is hard to imagine how something that is just a point, that has no shape and takes up no space, could exist in different states or configurations...String theory resolves this paradox, because it says that the end of the process of reductionism is that the most fundamental entities are one dimensional strings and not points...it is [the] different modes of vibration of the string that are understood in string theory as being the different elementary particles," (The Life of the Cosmos, 1997, p65).
Gervais, however, points out that strings are actually composed of quimballs, which, in turn, are composed of two-for-quarkels and a strumpet. It's coruscating stuff from Reading's finest.
Ricky Gervais Radio 5 String theory Quimballs