Question

The meristem present at the base of the internode is
A) Lateral meristem
B) Intercalary Meristem
C) Apical Meristem
D) All of the above

Answer 1

Hint: In a plant, at intervals called nodes, lateral buds and leaves grow out of the stem. Internodes are considered the intervals on the stem between the nodes.

Complete Answer:
- The word "meristem" was coined by Carl Wilhelm von Nägeli. Meristematic tissue comprises undifferentiated cells, which form the building blocks of specialised plant structures. Meristematic tissues contain living cells of different shapes. They have a large nucleus without a vacuole. The cells do not have any intercellular space. The region where these cells live is known as meristem. Meristematic tissue cells selectively divide into specialised structures such as buds of leaves and fruits, tips of roots and shoots, etc. These cells help to expand the duration and diameter of the plant.

- Intercalary meristems are found at the base of the stem or leaf internodes. It assists in the elongation and development of plants in the nodes and internodes of stems and leaves as well as in the longitudinal growth of stems, leaves and grasses. The increase in the duration of the petiole is due to the intercalary meristem’s activity. They are called primary meristems because they aid in the primary growth of the plants especially for the lengthening of the plant.

- Lateral Meristem is found on the side of the stems and roots. It helps to increase the thickness of the plant. Apical Meristem is found at the tips of the roots and shoots and tends to raise the height of the plants.

So, the correct option is B, the Intercalary meristems.

Note: Meristematic tissue is a plant tissue that has the capacity to disassociate actively during its lifespan. Meristematic tissue is typically located in root and shoot apexes and is in a persistent state of division.