Exercises
The transverse section of a plant material shows the following anatomical features - (a) the vascular bundles are conjoint, scattered and surrounded by a sclerenchymatous bundle sheaths. (b) phloem parenchyma is absent. What will you identify it as?
The given anatomical features — conjoint vascular bundles that are scattered (not in a ring) and enclosed by sclerenchymatous bundle sheaths, combined with the absence of phloem parenchyma — are the defining characteristics of a monocotyledonous stem.
Reasoning:
- Conjoint vascular bundles (xylem and phloem on the same radius) are found in stems and leaves, not roots.
- Scattered arrangement (as opposed to a ring) is exclusive to monocot stems.
- Sclerenchymatous bundle sheath surrounding each vascular bundle is a hallmark of monocot stems.
- Absence of phloem parenchyma is a specific characteristic of monocot stems.
Therefore, the plant material is a monocotyledonous stem (e.g., maize/Zea mays stem).
Answer: It is a monocotyledonous stem. The scattered conjoint vascular bundles with sclerenchymatous bundle sheaths and absent phloem parenchyma are the diagnostic features of a monocot stem.