Which character among the angiosperms is most important taxonomically to differentiate it from the gymnosperms?

Options

A. Triploid endosperm
B. Attractive petals
C. Presence of vessels in xylem
D. Seeds enclosed in fruit

Explanation

To differentiate angiosperms from gymnosperms, we need to focus on the key taxonomic characters that define these two groups of seed-producing plants. Here's a step-by-step breakdown of the most important distinguishing feature:

### Step-by-Step Solution:

1. **Understanding Seed Structure**:
- Angiosperms are known as flowering plants, and one of their defining characteristics is that they produce seeds that are enclosed within a fruit (ovary).
- In contrast, gymnosperms have naked seeds that are not enclosed in any fruit structure.

2. **Significance of Enclosed Seeds**:
- The presence of seeds enclosed in a fruit is a significant evolutionary advancement. It provides protection to the seeds and aids in their dispersal.
- This feature allows angiosperms to have a more efficient reproductive strategy compared to gymnosperms.

3. **Double Fertilization**:
- Angiosperms undergo a process called double fertilization, which results in the formation of a triploid endosperm that nourishes the developing embryo.
- Gymnosperms do not have this process, which is another key difference.

4. **Xylem Structure**:
- In terms of vascular tissue, angiosperms possess vessels in their xylem, which allows for more efficient water transport.
- Gymnosperms typically lack these vessels and rely on tracheids for water conduction.

5. **Classification**:
- Taxonomically, the most important feature that differentiates angiosperms from gymnosperms is the presence of seeds enclosed in fruits (ovaries) as opposed to naked seeds in gymnosperms.

### Final Answer:
The most important taxonomic character that differentiates angiosperms from gymnosperms is the presence of seeds enclosed within a fruit (ovary).