Which of these statements is false ?

Options

A. All prokaryotes classified under kingdom Monera have a cell wall.
B. All viroids have single - stranded RNA as the genetic material.
C. All prions don't have nucleic acid as their genetic material.
D. Unicellular plants have been place in kingdome Protista by Whittaker.

Answer

To determine which statement is false among the provided options, we will analyze each statement one by one.

### Step-by-Step Solution:

1. **Statement Analysis:**
- **Statement 1:** "All prokaryotes classified under kingdom Monera have a cell wall."
- **Analysis:** This statement is incorrect. While most prokaryotes, specifically bacteria, do have a cell wall, there are exceptions. For instance, Mycoplasma, which is a member of the Monera kingdom, lacks a cell wall. Therefore, this statement is false.

2. **Statement 2:** "All viroids have single-stranded RNA as a genetic material."
- **Analysis:** This statement is true. Viroids are indeed infectious agents that consist solely of a short strand of circular single-stranded RNA and do not have a protein coat.

3. **Statement 3:** "All prions are infectious agents that cause neurological diseases."
- **Analysis:** This statement is true. Prions are misfolded proteins that can induce other proteins to misfold, leading to diseases such as Bovine Spongiform Encephalopathy (BSE). They do not contain any nucleic acids, which is a characteristic of prions.

4. **Statement 4:** "Unicellular plants have been placed in the kingdom Protista by Whittaker."
- **Analysis:** This statement is true. The kingdom Protista includes a diverse group of unicellular eukaryotic organisms, including algae and protozoa, as classified by Robert Whittaker.

### Conclusion:
After analyzing all the statements, we find that the first statement is false. Therefore, the answer to the question "Which of these statements is false?" is:

**Answer:** Statement 1 is false.

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