Nissl granule is a specialized structure in neuron formed by modification of:
- A. Golgi bodies & Smooth ER
- B. Peroxisome & Mitochondria
- C. Lysosome & Vacuole
- D. Ribosome & Rough ER
Explanation
Nissl granules are dense stacks of rough endoplasmic reticulum studded with ribosomes, which is why they stain so darkly and why they are concentrated in the cell body where protein synthesis for the whole neurone takes place. Smooth ER carries no ribosomes and handles lipid synthesis instead. Their disappearance after injury, called chromatolysis, is a standard sign of nerve cell damage.
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