Question

Why do meristematic cells have a prominent nucleus and dense cytoplasm but they lack vacuoles.
A. No need for storage
B. No space for vacuoles
C. Cells cannot divide possessing vacuoles
D. None of the above

Answer 1

Meristematic tissues or cells are simply actively dividing cells and they remain forever young throughout the life of the plant. These refer to living tissues having undifferentiated cells that form the building blocks of all the specialized plant’s structures such as leaves, stem, and roots.

Complete answer: As these are actively dividing cells, the newly formed cells are after mitotic divisions are pushed away from the zone of active division. These newly formed take their function and shape accordingly.
A plant has four types of meristems in them:
a. Apical meristems- Located at the opposite ends of the plants in the tips of roots and shoots. Cell divisions and cellular enlargements of these help the plant to increase in length above and below parts of the plants. These are known as primary meristems.
b. Lateral meristems- These are known to increase the girth of the plants. These tissues are responsible for increasing the diameter of tree trunks. Three types of lateral meristem include:
i. Vascular cambium- some plants are known to grow in diameter by producing new tissues laterally, which is known to extend from tips of the shoots to the tips of the roots. Includes some annual plants.
ii. Cork cambium- These are known to be produced in the bark of roots and stems of woody plants in which they produce cork cells. It originates just under the epidermis of the primary body and in some species running along vascular cambium in the form of cylinders.
iii. Intercalary meristems- These are present in grasses present along the stem near the nodes. Divisions in this push the stem upwards.
Meristematic cells as such are known to be so much actively dividing cells so they need a large nucleus in them and a large number of cytoplasmic contents. They need both of these for dividing. Meristematic cells are known to lack vacuoles as they don’t carry the function of storage of food as they divide continuously. These cells don’t need any food so they lack food vacuoles as they are metabolically active. These cells barely have space in between them as the cells are so compactly packed.
So, the correct answer is option” A”

Note: Cells within these meristematic tissues are known to be self-renewing as each time when dividing one cell remains closely related to the parent and the other cell can become part of another plant structure. When a plant is injured meristematic cells are known for the healing process by dividing cells.