Draw a labelled diagram of a mature embryo sac. Why does a pollen grain possesses two male gametes? Explain.

Explanation

### Step-by-Step Solution:

#### Part 1: Drawing a Labeled Diagram of a Mature Embryo Sac

1. **Understanding the Structure**: A mature embryo sac is an eight-nucleated and seven-celled structure. It consists of three antipodal cells, two synergids, one egg cell, and one central cell containing two polar nuclei.

2. **Drawing the Diagram**:
- Start by drawing a large oval shape to represent the embryo sac.
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