In plants, which type of tissue consists of cells that have permanently lost the capacity to divide and instead perform specialised functions?

Introduction / Context:
Plant bodies are built from two broad categories of tissues: meristematic tissues, which are responsible for growth through cell division, and permanent tissues, whose cells have differentiated to perform specific functions. Knowing which tissue type loses the ability to divide is fundamental to understanding plant growth and development and is a frequent topic in school level botany. This question asks you to identify that tissue type.

Given Data / Assumptions:

We are comparing tissue types in plants based on their ability to undergo cell division. The question mentions cells that have lost the capacity for further division. Options contrast meristematic tissue, permanent tissue and other combinations. We assume standard definitions where meristems are growth regions and permanent tissues are differentiated.

Concept / Approach:
Meristematic tissues contain small, actively dividing cells that are undifferentiated and capable of repeated mitosis. These tissues are found at root and shoot tips, in cambium and other growth regions. As meristematic cells differentiate, they enlarge and take on specific shapes and functions, forming permanent tissues such as parenchyma, collenchyma, sclerenchyma, xylem and phloem. Once fully differentiated, most permanent tissue cells lose the ability to divide and instead focus on conduction, support, storage or photosynthesis. Therefore, the plant tissues whose cells have lost the capacity for division are called permanent tissues.

Step-by-Step Solution:
Step 1: Recall that meristematic cells are small, thin-walled, with dense cytoplasm and large nuclei, adapted for frequent mitosis. Step 2: Understand that these cells give rise to all other tissues in the plant body through division and differentiation. Step 3: Recognise that as cells mature into permanent tissues, they become specialised in tasks such as support, photosynthesis or transport. Step 4: Note that during this differentiation, most permanent tissue cells lose the power of further division. Step 5: Therefore, the tissue type described in the question, whose cells have lost their division capacity, is permanent tissue, not meristematic tissue.

Verification / Alternative check:
You can verify this by thinking of examples. Xylem vessels and tracheids, part of permanent complex tissues, are dead at maturity and cannot divide. Sclerenchyma fibres become thick walled and rigid, losing any ability for cell division. In contrast, cells at the root and shoot tips or in the vascular cambium remain capable of mitosis and are classified as meristematic. Textbooks consistently state that permanent tissues arise from meristems and are made of cells that generally lose their dividing ability, which directly matches the question statement.

Why Other Options Are Wrong:
Meristematic tissue, by definition, consists of cells that actively divide and therefore has not lost the capacity for cell division. Embryonic tissue in seeds is a stage where cells are still capable of division when germination begins, so it does not fit the description of permanent loss of division capacity. Saying both meristematic and permanent tissues would be contradictory because they differ precisely in this property. The option none of these is incorrect because permanent tissue accurately satisfies the condition stated in the question.

Common Pitfalls:
Students sometimes confuse the names and think that meristematic means permanent because of unfamiliarity with botanical terminology. Another pitfall is to overgeneralise and assume that all plant cells retain some capacity to divide, which is not true after differentiation. To avoid these mistakes, remember a simple contrast: meristematic equals dividing and growing, while permanent equals differentiated and non dividing. This clear mental picture helps in solving many plant tissue questions easily.

Final Answer:
The tissue whose cells have lost the capacity for further division and perform specialised functions is permanent tissue.