Matching labels to dicot plant tissue structures

Steps:

• Identify root features: central vascular tissue is xylem (label 1), with endodermis as inner boundary layer (label 3).
• Examine stem: outer vascular tissue in bundles is phloem (label 2), surrounded by cortex (label 4).
• Analyze leaf: outermost protective layer is epidermis (label 5), with internal parenchyma-like mesophyll akin to cortex.
• Cross-check options: only D aligns all labels with standard dicot root (xylem core, endodermis), stem (phloem), and leaf (cortex, epidermis) positions.

Why D is correct:

• Dicot root has central xylem (1) and endodermis (3) as a casparian strip layer; stem phloem (2) transports sugars outward; leaf epidermis (5) covers surfaces, cortex (4) provides support.

Why the others are wrong:

• A: Labels phloem (1,2) incorrectly in root center, which is xylem.
• B: Misidentifies root center as phloem (1) instead of xylem; leaf parenchyma (4) not endodermis (5).
• C: Places parenchyma (2) where stem phloem belongs; endodermis absent in leaf.

Final answer: D