Organelle Membrane Layers

Steps:

• Recall that chloroplasts have an outer and inner membrane from endosymbiotic origins.
• Note mitochondria also possess a double membrane envelope for energy production.
• Identify the nucleus as enclosed by a nuclear envelope consisting of two lipid bilayers.
• Compare these to the given choices to match the double membrane pattern for all three.

Why D is correct:

• Eukaryotic organelles like chloroplasts, mitochondria, and the nucleus each evolved with double membranes, as defined by the endosymbiotic theory and nuclear envelope structure.

Why the others are wrong:

• A: Chloroplast and mitochondrion have double, not single, membranes.
• B: All three structures have double, not single, membranes.
• C: Mitochondrion and nucleus have double, not single, membranes.

Final answer: D