Practice question

Overtopping describes fundamental evolutionary process where one branch of initially isotomous dichotomy grows more vigorously than the sister branch, establishing pseudomonopodial system with dominant main axis and subordinate laterals that can become leaf precursors. This unequal development, combined with subsequent planation bringing branches into plane and webbing forming lamina, converts primitive three-dimensional telome trusses into flattened megaphyll precursors. Dichotomy refers to equal branching, enation to emergence of small nonvascular leaf protrusions, webbing to parenchymatous tissue development between telomes. This structural framework illustrates phylogenetic relationships and adaptive significance highlighted in competitive examinations focusing on comparative plant morphology and systematics.