Study the following statements.
1. Prokaryotes do not have nucleus. 2. A single cell can perform all the functions in a unicellular organism. 3. Blue-green algae are the examples of prokaryotes. 4. Eukaryotes do not have well-organised nucleus with a nuclear membrane.
The correct statements are

Options

A. 1,3 and 4
B. 2, 3 and 4
C. 1, 2 and 3
D. 1, 2 and 4

Explanation

To determine which statements about prokaryotes and eukaryotes are correct, we will analyze each statement one by one.

### Step-by-step Solution:

1. **Statement 1: Prokaryotes do not have a nucleus.**
- This statement is **incorrect**. Prokaryotes do not have a well-defined nucleus; instead, they have a nucleoid region where their genetic material is located. However, they do not possess a membrane-bound nucleus like eukaryotes.

2. **Statement 2: A single cell can perform all the functions in a unicellular organism.**
- This statement is **correct**. In unicellular organisms, such as amoeba or bacteria, a single cell is capable of performing all necessary life functions, including metabolism, reproduction, and response to the environment.

3. **Statement 3: Blue-green algae are examples of prokaryotes.**
- This statement is **correct**. Blue-green algae, also known as cyanobacteria, are indeed prokaryotic organisms. They lack a membrane-bound nucleus and are classified as bacteria.

4. **Statement 4: Eukaryotes do not have a well-organized nucleus with a nuclear membrane.**
- This statement is **incorrect**. Eukaryotes have a well-defined and organized nucleus that is enclosed by a nuclear membrane, which distinguishes them from prokaryotes.

### Conclusion:
Based on the analysis:
- The correct statements are **2 and 3**.

### Final Answer:
The correct statements are 2 and 3.

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