Page 40 - Pharmacognosy 2 PG303
P. 40

Pharmacognosy-2 (PG303)                              Level 2                  Clinical Pharmacy-Pharm D



                                                    Fruit introduction


                 Definition:
                 It is developed ovary or ovaries of a single flower or of a whole inflorescence.
                 Fruit is a mature fertilized ovary.
                 function:
                  protect, nourish and insure the distribution of the seed.
                 Fruit composed of:
                 1-pericarp               2-seed

                    ➢ Pericarp composed of three layers:

                 1-exocarp (epicarp)=outer layer
                 2-Mesocarp=middle layer
                 3-endocarp= inner layer

                 Types of fruit:
                 1-True fruits: formed from the gynoecium
                 2-False fruits: other parts of the flower contribute to its formation
                    ➢ Parthenocarpy:
                  Development of fruit without fertilization, so the fruit is seedless.
                 Ex: pineapple, banana, cucumber, grape, orange, persimmon
                    ✓  Results from one of three causes:
                 1-lack of pollination
                 2-pollination occurs but fertilization does not
                 3-fertilization is followed by embryo (seed) abortion.
                 Thus, fruits of cucumber contain seed-like structures, but these structures lack an embryo and endosperm





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