Mark the incorrect statement -

Options

A. Ribosomes are non-membrane bound organelles found in all cells – both eukaryotic as well as prokaryotic.
B. Cells that have membrane bound nuclei are called eukaryotic whereas cells that lack a membrane bound nucleus are prokaryotic.
C. All eukaryotic cells are identical.
D. Animal cells have centrioles which are absent in almost all plant cells.

Answer

To determine which statement is incorrect, let's analyze each statement one by one:

1. **Statement 1**: "Ribosomes are non-membrane bound organelles found in all cells both prokaryotic as well as eukaryotic."
- **Analysis**: This statement is correct. Ribosomes are indeed non-membrane bound organelles and are found in both prokaryotic and eukaryotic cells. In prokaryotes, they are typically 70S, while in eukaryotes, they are larger, usually 80S.

2. **Statement 2**: "Cells that have membrane bound nuclei are eukaryotic."
- **Analysis**: This statement is also correct. Eukaryotic cells are characterized by having a membrane-bound nucleus, unlike prokaryotic cells, which do not have a true nucleus.

3. **Statement 3**: "All eukaryotic cells are identical."
- **Analysis**: This statement is incorrect. Eukaryotic cells can vary significantly in structure and function. For example, plant cells and animal cells have different organelles and functions, and even within the same organism, different cell types (like muscle cells and nerve cells) are not identical.

4. **Statement 4**: "Animal cells, centrioles, which are absent in almost all plant cells."
- **Analysis**: This statement is generally correct. Centrioles are found in animal cells and are involved in cell division. While some plant cells do have structures similar to centrioles, they are not present in most plant cells.

**Conclusion**: The incorrect statement is **Statement 3: "All eukaryotic cells are identical."**