Which of the following cell organelles does not have a double membrane layer?

Ribosomes are organelles responsible for protein synthesis in cells, and they do not have a double membrane layer. Unlike mitochondria and chloroplasts, which have two membranes, ribosomes are composed of protein and ribonucleic acid (RNA) and are not surrounded by a membrane. Chloroplasts, on the other hand, are organelles in plant cells that are responsible for photosynthesis, while mitochondria are organelles found in eukaryotic cells that are responsible for aerobic respiration. Both chloroplasts and mitochondria have a double membrane layer.