The most common type of embryo sac in angiosperm

Options

A. Polygonum
B. Oenothera
C. Adoxa
D. Plumbago

Answer

**Step-by-Step Text Solution:**

1. **Understanding the Question**: The question asks for the most common type of embryo sac found in angiosperms.

2. **Identifying Options**: The options provided are:
- A) Polygonum
- B) Inothera
- C) Adoxa
- D) Plumbago

3. **Defining the Embryo Sac**: The embryo sac is the female gametophyte in angiosperms, which develops from the megaspore.

4. **Common Type of Embryo Sac**: The most common type of embryo sac in angiosperms is the Polygonum type. This type is characterized by:
- It is an 8-nucleated embryo sac.
- It develops from the chalazal megaspore.
- It undergoes three nuclear divisions resulting in eight nuclei.

5. **Statistical Prevalence**: The Polygonum type is found in about 81% of flowering plant families, making it the most prevalent type.

6. **Historical Context**: The Polygonum type was first described by Strasburger in the species Polygonum divaricatum.

7. **Analyzing Other Options**:
- **Inothera**: This type is a monosporic, poronucleated embryo sac that develops from the micropilar megaspore, making it incorrect.
- **Adoxa and Plumbago**: Both are types of tetrasporic embryo sacs, which also makes them incorrect.

8. **Conclusion**: Based on the above analysis, the correct answer to the question is **A) Polygonum**.

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