A group of specialised nucellar cells between embryo sac and micropyle is

Options

A. Metastase
B. Mesostase
C. Epistase
D. Hypostase.

Answer

To solve the question regarding the group of specialized nucellar cells located between the embryo sac and the micropyle, we can follow these steps:

### Step 1: Understand the Terminology
- **Embryo Sac**: This is the female gametophyte in seed plants, which contains the egg cell and other cells involved in fertilization.
- **Micropyle**: This is a small opening in the ovule that allows the pollen tube to enter for fertilization.

### Step 2: Identify the Options
The options provided are:
- A) Metastase
- B) Mesostase
- C) Epistase
- D) Hypostase

### Step 3: Analyze Each Option
- **Metastase**: This term does not relate to the cells between the embryo sac and micropyle.
- **Mesostase**: This is also not a recognized term in this context.
- **Epistase**: This refers to the specialized nucellar cells located between the embryo sac and the micropyle. These cells are characterized by being thick cutinized and forming a cap.
- **Hypostase**: This refers to a group of specialized nucellar cells located between the embryo sac and the chalazal region (chalaza), which is not the correct answer for this question.

### Step 4: Conclusion
Based on the analysis, the correct answer is **C) Epistase**. These cells are specifically positioned between the embryo sac and the micropyle, fulfilling the criteria mentioned in the question.

### Final Answer
The group of specialized nucellar cells between the embryo sac and micropyle is **Epistase**.

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