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

Gujarat BoardEnglish MediumSTD 12 ScienceBIOLOGYSexual Reproduction In Flowering Plants4 Marks
Question
Write a short note on endosperm development.
✓

Answer

→ Endosperm development precedes embryo development.
→ The primary endosperm cell divides repeatedly and forms a triploid endosperm tissue.
→ The cells of this tissue are filled with reserve food materials and are used for the nutrition of the developing embryo.
→ In the most common type of endosperm development, the PEN undergoes successive nuclear divisions to give rise to free nuclei. This stage of endosperm development is called free-nuclear endosperm.
→ Subsequently cell wall formation occurs and the endosperm becomes cellular.
→ The number of free nuclei formed before cellularisation varies greatly.
→ The coconut water from tender coconut that you are familiar with, is nothing but free- nuclear endosperm (made up of thousands of nuclei) and the surrounding white kernel is the cellular endosperm.
→ Endosperm may either be completely consumed by the developing embryo (e.g., pea, groundnut, beans) before seed maturation or it may persist in the mature seed (e.g. castor and coconut) and be used up during seed germination.

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