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Sexual Reproduction in Flowering Plants — BIOLOGY STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 ScienceBIOLOGYSexual Reproduction in Flowering Plants3 Marks
Question
Fertilisation is essential for production of seed, but in some angiosperms, seeds develop without fertilisation.
  1. Give an example of an angiosperm that produces seeds without fertilisation Name the process.
  2. Explain the two ways by which seeds develop without fertilisation.
✓

Answer

A. Members of Asteraceae/grasses/citrus/mango, apomixis.

B. Two ways -

  1. In some species, the diploid egg cell is formed without reduction division and develops into embryo without fertilisation.
  2. More often, as in many citrus and mango varieties some of the nucellar cells surrounding the embryo sac start dividing, protrude into the embryo sac and develop into the embryos.

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