**Question:** Nissl's granules contains

**Core Concept:** Nissl's granules, also known as neuroglia or neuroglial granules, are structures within neurons that play a vital role in the storage of proteins, nucleic acids, and other macromolecules necessary for proper neuronal function. They are responsible for maintaining the cell's osmotic balance and energy supply. Nissl granules are composed of glycogen, ribosomes, and mitochondria, which are essential for protein synthesis and energy production within the neuron.

**Why the Correct Answer is Right:** Nissl granules are named after the German neuropathologist, Gustav Nissl, who first described them in 1904. They are composed of three main components: glycogen (a carbohydrate storage), ribosomes (the sites of protein synthesis), and mitochondria (the energy-producing organelles). These components work together to enable the neuron to efficiently store macromolecules, maintain osmotic balance, and provide energy for various cellular processes, thus ensuring proper neuronal function.

**Why Each Wrong Option is Incorrect:**

A. This option refers to lipofuscin granules, which are different structures found in neurons and other cells. Lipofuscin granules are lipid-containing pigment granules that accumulate with age and are associated with cell aging and degeneration.

B. This option refers to myelin granules, which are part of the myelin sheath that surrounds axons in the central nervous system (CNS). Myelin granules are composed of lipids, proteins, and oligodendrocytes, not found within neurons.

C. This option refers to Nissl bodies, a different structure found in glial cells like astrocytes and oligodendrocytes. Nissl bodies contain glycogen and other macromolecules for energy storage and macromolecule synthesis in these glial cells, not neurons.

D. This option refers to synaptic vesicles, which are small organelles found in presynaptic terminals of neurons. Synaptic vesicles store neurotransmitters and facilitate neurotransmission, not Nissl granules.

**Core Concept:** Nissl granules are a key component of neurons, specifically involved in protein synthesis, energy production, and macromolecule storage, ensuring proper neuronal function and survival.

**Why Each Wrong Option is Incorrect:**

A. Synaptic vesicles are found in presynaptic terminals of neurons and are involved in neurotransmission, not Nissl granules.

B. Lipofuscin granules are lipid-containing pigment granules found in neurons and other cells, not Nissl granules.

C. Nissl bodies are found in glial cells like astrocytes and oligodendrocytes, not neurons.

D. Nissl granules are involved in energy storage and macromolecule synthesis in glial cells, not neurons.

**Why the Correct Answer is Right:**

Nissl granules, also known as Nissl granules or Nissl substance, are found in the cytoplasm of neurons. They are crucial for the neuron's functions, such as energy production, macromolecule synthesis, and storage. Nissl granules, composed