What is coleorhiza?

Answer

**Step-by-Step Solution:**

1. **Understanding the Context**: The term "coleorhiza" is related to the structure of the embryo in flowering plants, specifically in monocotyledons.

2. **Identifying the Embryo Structure**: In monocotyledons, the embryo consists of a single cotyledon. This cotyledon is often referred to as the "scutellum" in the grass family.

3. **Locating the Radical**: At the lower end of the monocot embryo, there is a structure known as the radical, which is the part that will develop into the root.

4. **Understanding the Protective Sheath**: The radical is protected by a sheath, which is an undifferentiated covering. This protective covering is called the coleorhiza.

5. **Defining Coleorhiza**: Therefore, the coleorhiza is defined as the protective cap that covers the radical (the embryonic root) in monocotyledonous plants.

6. **Conclusion**: In summary, coleorhiza is a crucial structure in monocot embryos that serves to protect the developing root.

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