Which structure is NOT found in a typical prokaryotic cell?

• A. Cell wall (in many species)
• B. Plasma membrane
• C. Membrane-bound nucleus
• D. Ribosomes

Answer: (C)

Verified step by step guidance

1. Step 1: Understand the basic structures of a typical prokaryotic cell. Prokaryotic cells generally have a plasma membrane, ribosomes, and often a cell wall, but they lack membrane-bound organelles.
2. Step 2: Recall that membrane-bound organelles are structures enclosed by lipid bilayers, such as the nucleus, mitochondria, and endoplasmic reticulum, which are characteristic of eukaryotic cells.
3. Step 3: Identify that the nucleus is a membrane-bound organelle that contains the cell's genetic material, and it is absent in prokaryotic cells.
4. Step 4: Compare the options given: cell wall (present in many prokaryotes), plasma membrane (present in all cells), ribosomes (present in all cells), and membrane-bound nucleus (absent in prokaryotes).
5. Step 5: Conclude that the structure NOT found in a typical prokaryotic cell is the membrane-bound nucleus, because prokaryotes have their DNA free in the cytoplasm, not enclosed within a membrane.