Nucellus is mass of cells enclosed within integuments.

Answer

**Step-by-Step Solution:**

1. **Understanding Nucellus**: The nucellus is a tissue found within the ovule of seed plants. It is comprised of a mass of cells that play a crucial role in the reproductive process.

2. **Integuments**: The integuments are layers of protective tissue that surround the nucellus. They form the outer covering of the ovule and are important for protecting the developing seed.

3. **Relationship Between Nucellus and Integuments**: The statement in question asserts that the nucellus is a mass of cells enclosed within integuments. This means that the nucellus is indeed surrounded by the integument layers.

4. **Function of Nucellus**: The primary function of the nucellus is to give rise to megaspore mother cells (also known as megasporocytes). These cells undergo meiosis to form megaspores, which eventually develop into the female gametophyte.

5. **Conclusion**: Since the nucellus is indeed a mass of cells that is enclosed by integuments, the statement is confirmed to be true.

**Final Answer**: The statement "Nucellus is a mass of cells enclosed within integuments" is true.

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