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🔬 Biology  ·  Sexual Reproduction in Flowering Plants  ·  NEET

Hybrid seed production requires male sterility in the seed parent. CMS (cytoplasmic male sterility) is:

  • A A nuclear recessive mutation that is inherited generally according to standard Mendelian segregation ratios across generations
  • B Sterility caused by mitochondrial genes that prevent pollen development (used in hybrid seed production in rice, maize, sorghum)
  • C A condition that is caused specifically by deletion of particular genes located on the X chromosome itself
  • D A condition induced largely by a persistent, latent viral infection that specifically targets the developing anther tissue

Correct answer: B. Sterility caused by mitochondrial genes that prevent pollen development (used in hybrid seed production in rice, maize, sorghum)

Explanation: CMS: mitochondrial gene (non-Mendelian) causes pollen abortion. Nuclear restorer genes (Rf) can restore fertility. Used in F1 hybrid seed production: CMS female x normal male -- no manual emasculation needed.

Concept context

Flower structure, pollination, double fertilization, and seed/fruit development — the highest-scoring Class 12 biology chapter in NEET.

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