Which of the following statements is not true for a eukaryotic cell ?

Options

A. It has two envelope organisation
B. Nuclear DNA is linear and associated with histone proteins
C. The amount of DNA remains the same throughout the cell cycle
D. Cytoplasm usually shows streaming movement

Answer

To determine which statement is not true for a eukaryotic cell, we will analyze each of the provided statements one by one.

### Step 1: Analyze the First Statement
**Statement:** Eukaryotic cells have a double envelope organization.
**Analysis:** This statement is true. Eukaryotic cells possess a plasma membrane and a nuclear membrane, which constitutes a double envelope organization.

**Hint:** Remember that eukaryotic cells have both a plasma membrane and a nuclear membrane.

### Step 2: Analyze the Second Statement
**Statement:** Nuclear DNA is linear and associated with histone proteins.
**Analysis:** This statement is also true. In eukaryotic cells, the DNA is indeed linear and is wrapped around histone proteins, forming structures called nucleosomes.

**Hint:** Consider the structure of DNA in eukaryotes versus prokaryotes.

### Step 3: Analyze the Third Statement
**Statement:** The amount of DNA remains the same throughout the cell cycle.
**Analysis:** This statement is not true. The amount of DNA does not remain constant throughout the cell cycle. It is the same during the G1, G2, and M phases, but during the S phase, DNA replication occurs, doubling the amount of DNA.

**Hint:** Recall the different phases of the cell cycle and what happens during the S phase.

### Step 4: Analyze the Fourth Statement
**Statement:** Cytoplasm usually shows streaming movement.
**Analysis:** This statement is true. In eukaryotic cells, the cytoplasm often exhibits streaming movements, which can facilitate the transport of materials within the cell.

**Hint:** Think about the dynamic nature of the cytoplasm in eukaryotic cells.

### Conclusion
After analyzing all the statements, the statement that is not true for a eukaryotic cell is the third statement: "The amount of DNA remains the same throughout the cell cycle."

**Final Answer:** The correct answer is option 3.