Within each ovale a haploid embryo sac usually contains eight nuclei.

Answer

**Step-by-Step Solution:**

1. **Understanding the Structure**: In flowering plants (angiosperms), the ovule contains a specialized structure known as the embryo sac. This structure is crucial for reproduction.

2. **Composition of the Embryo Sac**: The embryo sac is typically described as being 7-celled and 8-nucleate. This means that while there are 7 distinct cells, they collectively contain 8 nuclei.

3. **Cell Types in the Embryo Sac**:
- **Antipodal Cells**: At one end of the embryo sac, known as the chalazal end, there are 3 cells called antipodal cells. Each of these cells contains one nucleus, contributing a total of 3 nuclei.
- **Central Cell**: In the center of the embryo sac, there is one large cell that contains 2 polar nuclei. This is referred to as the central cell, contributing an additional 2 nuclei.
- **Egg Cell and Synergids**: At the opposite end of the embryo sac, there is one egg cell (female gamete) and 2 synergid cells. The egg cell has one nucleus, and each synergid has one nucleus, contributing a total of 3 nuclei.

4. **Counting the Nuclei**:
- Antipodal cells: 3 nuclei
- Central cell: 2 nuclei
- Egg cell + Synergids: 3 nuclei
- Total: 3 (antipodal) + 2 (central) + 3 (egg and synergids) = 8 nuclei

5. **Conclusion**: Therefore, the statement that within each ovule, a haploid embryo sac usually contains 8 nuclei is true.

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