Roughly how much of the root length do the zones of division, elongation and maturation occupy?

1. The three root zones are packed into a very short stretch behind the tip. 2. All three lie within the first centimetre or so of the root tip. 3. So the correct scale is roughly one centimetre, not ten. 4. Saying the whole young root would mean cells never stop dividing along its length, which contradicts the zoned arrangement. 5. The lower half is a distance measured from the wrong end, since the zones are measured back from the tip. 6. This compactness matters in practice because damage to the last centimetre of a root tip removes all three zones at once. _Source: OpenStax Biology (1st ed., CC BY 4.0), Ch 30 "Plant Form and Physiology", section 30.3 Roots_