Practice question

Determinate inflorescence hallmark is conversion of peduncle apex into terminal flower that stops further apical growth; lateral branches may continue but main axis is closed and finite. This defining feature characterizes cymose inflorescence, not racemose where axis continues indefinitely as seen in mustard, radish and snapdragon racemes. Umbel is racemose type where pedicels arise from single point but axis remains indeterminate condensed, spike indeterminate sessile flowers. Cymose termination explains limited flower number, basipetal opening sequence and terminal flower generally largest due to early resource acquisition and longer developmental period.