Concept: This question tests your knowledge of the specialized structures found within different cell types, specifically focusing on the unique components of neurons.

Why (B) is correct: Nissl's granules (also known as Nissl bodies) are large granular bodies found in the cytoplasm of neurons (nerve cells). They are composed of rough endoplasmic reticulum (RER) and free ribosomes, and their primary function is protein synthesis, which is crucial for the growth and regeneration of nerve fibers and the production of neurotransmitters.

Why other options are wrong:
A) Liver cells have abundant smooth endoplasmic reticulum for detoxification and rough ER for plasma protein synthesis, but they do not contain Nissl's granules.
C) Kidney cells are involved in filtration and reabsorption and have specialized structures like microvilli, but not Nissl's granules.
D) Heart muscle cells are specialized for contraction and contain abundant myofibrils and mitochondria, but lack Nissl's granules.

Common Mistake: Students might confuse Nissl's granules with other cellular inclusions or organelles found in different cell types.

NEET Tip: Remember that Nissl's granules are a characteristic feature of neurons, indicating their high metabolic activity and protein synthesis requirements.

Correct Answer: (B)