Which structure is described as the membrane that surrounds and protects the cell?

• A. Cell wall
• B. Nuclear envelope
• C. Cytoskeleton
• D. Plasma membrane (cell membrane)

Answer: (D)

Verified step by step guidance

1. Step 1: Understand the function of each structure listed in the options. The cell wall provides rigid support and protection but is found mainly in plant cells, fungi, and some prokaryotes.
2. Step 2: Recognize that the nuclear envelope is a double membrane that surrounds the nucleus, protecting the genetic material inside, but it does not surround the entire cell.
3. Step 3: Know that the cytoskeleton is a network of protein fibers inside the cell that provides shape, support, and facilitates movement, but it is not a membrane.
4. Step 4: Identify that the plasma membrane (also called the cell membrane) is the lipid bilayer membrane that surrounds the entire cell, controlling what enters and leaves, and protecting the cell.
5. Step 5: Conclude that the plasma membrane is the correct structure described as the membrane that surrounds and protects the cell.