Q.Draw a neat labelled diagram: T. S. of dicot stem.

Step 1. Draw a large circle for the stem's transverse section.

Step 2. Mark the outer boundary as the epidermis, adding a cuticle line and one or two hair-like trichomes projecting outward.

Step 3. Just inside, draw 3-5 compact layers of cells with no gaps and label this hypodermis (collenchyma).

Step 4. Inside the hypodermis, draw a wider band of larger, more loosely arranged cells with visible gaps, and label this the general cortex (parenchyma), noting stored starch grains if desired.

Step 5. Draw a single ring of barrel-shaped cells at the inner boundary of the cortex and label it endodermis/starch sheath.

Step 6. Just inside, draw patches of small, thick-walled cells sitting directly over where each vascular bundle will be, and label this pericycle ('hard bast').

Step 7. Arrange a ring of separate oval vascular bundles evenly spaced around the stele; within each bundle, draw xylem toward the centre, a thin cambium line in the middle, and phloem toward the outside — label the whole bundle as conjoint, collateral, open. …

Build the diagram as concentric zones outside-in, ending with the single ring of open collatera …

• Drawing the vascular bundles scattered instead of in a single ring (that would be the monocot-stem pattern). …