Question 2. As quartz crystals "grow," new silicon dioxide molecules are aligned alongside the previous surfaces. Likewise, as aluminum silicates and other components of clay are dissolved and precipitate out, they too align with previous molecules, even perpetuating cracks and faults. Technically, these are self-replicating molecular assemblages and yet the quartz or clay has not risen to become "life." What feature(s) of DNA makes it different from quartz and clay?