- A Endosperm size alone, with little reference to underlying hybrid genetic compatibility between species involved in general practice as frequently described
- B Why interspecific hybrids often fail due to imbalanced maternal:paternal genomic contributions to endosperm (2m:1p required), controlled by imprinted genes
- C How starch granules are synthesized and subsequently packaged within the developing endosperm tissue structure itself in most textbook accounts during normal conditions
- D Embryo dormancy mechanisms that are triggered largely independently of any underlying endosperm genetic factor present as generally observed in typical laboratory settings
Correct answer: B. Why interspecific hybrids often fail due to imbalanced maternal:paternal genomic contributions to endosperm (2m:1p required), controlled by imprinted genes
Explanation: EBN (Endosperm Balance Number, Johnston): endosperm requires 2 maternal:1 paternal genome contributions (2:1 ratio). Imprinted genes in endosperm control this. Wrong ratio causes endosperm failure and hybrid inviability.
Concept context
Flower structure, pollination, double fertilization, and seed/fruit development — the highest-scoring Class 12 biology chapter in NEET.
Read the full Sexual Reproduction in Flowering Plants notes →