Which one of the following structures is not present in a prokaryotic cell ?
Cell wall
Ribosomes
Nucleus
Plasma membrane
Answer is Right!
Answer is Wrong!
This question was previously asked in
UPSC NDA-1 – 2023
The correct answer is C) Nucleus.
Prokaryotic cells (like bacteria and archaea) are characterized by the absence of membrane-bound organelles. The nucleus is a membrane-bound organelle that houses the genetic material in eukaryotic cells. In prokaryotic cells, the genetic material (usually a single circular chromosome) is located in a region called the nucleoid, but it is not enclosed within a membrane. Cell walls are typically present in most prokaryotes, providing structural support. Ribosomes are present in prokaryotic cells and are essential for protein synthesis (prokaryotic ribosomes are smaller, 70S, compared to eukaryotic 80S). The plasma membrane (cell membrane) is a fundamental component present in all types of cells, both prokaryotic and eukaryotic, enclosing the cytoplasm.