Draw a longitudinal section of a post-pollinated pistil showing entry of Pollen, tube into a mature embryo-sac. Label filiform apparatus, chalazal end, Hilium, antipodals, male gametes and secondary nucleus.

Explanation

### Step-by-Step Solution:

1. **Draw the Outline of the Pistil**: Start by drawing the longitudinal section of a pistil. This should include the ovary, style, and stigma. The ovary is the part where the embryo sac is located.

2. **Indicate the Entry of the Pollen Tube**: Draw a pollen tube entering the ovary. The pollen tube should be shown extending from the stigma down through the style into the ovary.

3. **Draw the Mature Embryo Sac**: Inside the ovary, draw the mature embryo sac. This should be an elongated structure that represents the female gametophyte.

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