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Difficulty: HardReproductive Systems and Processes in Organisms

Match each floral structure involved in angiosperm reproduction with its corresponding post-fertilization developmental fate or specialized physiological function.

  • Triploid primary endosperm nucleusDevelops into a nutritive tissue (endosperm) that feeds the developing embryo
  • Integuments of the ovuleDevelops into the protective seed coat (testa and tegmen)
  • Synergids and antipodalsDegenerate and dissolve after assisting pollen tube entry and double fertilization
  • Ovary wallDifferentiates into the protective pericarp of the mature fruit

Answer

Triploid primary endosperm nucleus matches with developing into nutritive endosperm tissue; Integuments of the ovule match with developing into the protective seed coat (testa and tegmen); Synergids and antipodals match with degenerating after assisting pollen tube entry; Ovary wall matches with differentiating into the protective pericarp of the fruit.
Each floral structure converts to its corresponding post-fertilization fate: the triploid primary endosperm nucleus (3n3n) forms the nutritive endosperm; ovule integuments harden into the seed coat; synergids and antipodals degenerate post-fertilization; and the maternal ovary wall forms the fruit pericarp.

Step-by-Step Solution

1
Analyze double fertilization products in angiosperms
The fusion of one sperm nucleus (nn) with the egg cell (nn) forms the zygote (2n2n), while the second sperm nucleus (nn) fuses with the polar nuclei (2n2n) to form the triploid primary endosperm nucleus (3n3n), which becomes the nutritive endosperm.
This identifies the developmental origin of angiosperm seed storage tissue.
2
Trace the structural transformation of the ovule layers
The maternal integuments surrounding the ovule dry and harden to form the seed coat (testa and tegmen).
Protective seed coats derive directly from ovular integumentary layers.
3
Determine the fate of non-gametic embryo sac cells
Synergids release chemical signals to guide pollen tube entry through the micropyle, while antipodals have nutritive roles prior to fertilization; both degenerate after double fertilization.
Non-essential female gametophyte cells undergo programmed cell death post-fertilization.
4
Differentiate between seed and fruit structural origins
The entire ovule becomes the seed, whereas the surrounding ovary wall develops into the fruit wall (pericarp).
The pericarp encloses the seeds and originates from the maternal ovary wall.

Key Concept

Double Fertilization and Post-Fertilization Structural Fates in Angiosperms
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Topics

Reproductive Systems and Processes in Organisms

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