Where are apical meristems located?

• A. Ends of shoots and roots
• B. Leaves
• C. Bark
• D. In trunks

Answer: (A)

Apical meristems drive primary growth by producing new cells that lengthen the plant, and they sit at the very tips of shoots and roots—the shoot apex and the root apex. In these regions, cells divide rapidly and give rise to the primary tissues: epidermis from the protoderm, ground tissues from the ground meristem, and the vascular tissues from the procambium. That elongation at the tips is what pushes the plant upward and downward into the soil. Other areas, like leaves, bark, and trunks, grow in other ways: leaves develop from primordia with their own growth processes; bark and trunks primarily increase diameter through lateral meristems such as the vascular cambium and cork cambium, not through apical growth. So the end tips of shoots and roots are the sites of apical meristems.