In a bisexual flower, if androecium and gynaecium mature at different times, the phenomenon is known as

1. The question describes a situation in a bisexual flower (having both male and female reproductive organs) where the androecium (male part - stamens) and gynoecium (female part - pistil/carpel) mature at different times. 2. This temporal separation of sexual maturity within the same flower is a mechanism to prevent self-pollination and promote cross-pollination. 3. This phenomenon is known as Dichogamy (Option A). 4. Dichogamy has two types: protandry (androecium matures first) and protogyny (gynoecium matures first). 5. Herkogamy (Option B) refers to the spatial separation of anthers and stigma within a flower to prevent self-pollination. 6. Heterogamy (Option C) can refer to alternation of generations or the production of different types of gametes, not typically used in this specific botanical context. 7. Monogamy (Option D) refers to having only one mate, irrelevant to flower maturation.