Biology · Anatomy of Flowering Plants · NEET
They differ by position and job. Apical meristem is at the tips (root apex and shoot apex) and increases LENGTH. Intercalary meristem is at the base of internodes and leaves (common in grasses and monocots) and also increases LENGTH. Lateral meristem (vascular cambium and cork cambium) lies along the sides and increases GIRTH (thickness). Apical and intercalary are primary meristems; lateral is a secondary meristem.
The LATERAL meristem. It includes the vascular cambium (fascicular and interfascicular) and the cork cambium (phellogen). These lie along the sides of stems and roots and add cells sideways, so the organ becomes thicker. This is called secondary growth. Apical and intercalary meristems only add LENGTH, not girth. NEET tests this exact point often.
Because of the INTERCALARY meristem. It sits at the base of the internodes and leaves, which is BELOW the point where grazing animals bite or a mower cuts. Since the dividing tissue is left behind after the cut, the grass keeps growing longer from the base. This is a very common NEET question (NEET 2019 asked exactly this).
Both apical and intercalary meristems are PRIMARY meristems. They appear early in the plant's life and cause primary growth (growth in length). The intercalary meristem is actually a part of the apical meristem left behind between mature tissues. Only the lateral meristem (cambium) is a SECONDARY meristem, causing secondary growth (girth).
It is located between mature (permanent) tissues, mainly at the BASE of internodes and at the base of leaves. It is common in grasses and other monocots. Because of this position, grasses can quickly grow back after the top is removed. Do not confuse it with the apical meristem, which is at the very tip of the shoot or root.
Regeneration of damaged growing grass following grazing is largely due to :-
Consider the following plant tissues. Identify the lateral meristems among the above. (A) Axillary buds (B) Fascicular vascular cambium (C) Interfascicular cambium (D) Cork cambium (E) Intercalary meristem
Try the real previous-year questions from this chapter — each with the answer and a full solution.
Three: apical (at tips), intercalary (at base of internodes and leaves) and lateral (along the sides). Apical and intercalary give length; lateral gives girth.
Apical and intercalary meristems cause primary growth (growth in length). Lateral meristem causes secondary growth (growth in girth/thickness).
No. It is mainly found in grasses and other monocots, at the base of internodes and leaves. It helps them regrow fast after grazing or mowing.
The vascular cambium (fascicular plus interfascicular cambium) and the cork cambium (phellogen). Both increase the girth of the plant during secondary growth.
Yes. The intercalary meristem is a portion of the apical meristem that gets left behind between mature tissues as the plant grows, so it is also a primary meristem.
