Is nissl granules absent in axon?

The Nissl’s granules are also present in dendrites of neurons. These are absent in axons and axon hillocks. So, the answer is, ‘Axon.

Does axon contain nissl substance?

The cytoplasm of the motoneurone soma contains several different types of organelle, the most prominent of which is the Nissl body. These bodies range from 0.5 to 3 μm in diameter and electronmicrographs show them to be composed of tightly packed arrays of endoplasmic reticulum.

What is the function of nissl’s granules in a nerve cell?

Nissl’s granules are of the rough endoplasmic reticulum (RER) and contain free ribosomes. They are responsible for the synthesis of proteins which flow along the dendrites and the axon and replace the proteins which are broken down during cellular activity.

Where are nissl granules found in neuron?

Nissl’s granules are found in neurons. They are made up of rough endoplasmic reticulum with plenty of ribosomes. So, their nature can be said as proteinaceous.

What are absent in axon?

An axon is the tubular process of the nerve cell, that carries impulses away from the cell body. It arises from the cyton at axon hillock. It has only neurofibrils. Here Nissls granules are absent.

Why are Nissl granules Basophilic?

Because ribosomes are rich in ribosomal RNA, they are strongly basophilic (“base-loving”). The dense accumulation of membrane-bound and free ribosomes in Nissl bodies results in their intense coloration by Nissl stains, allowing them to be seen with a light microscope.

Where the Nissl’s granules are found and what is their function?

Nissl granules are the substances found in the neurons which are a large granular type of body. These granules are rough endoplasmic reticulum (RER) with rosettes of free ribosomes. These are very useful for protein synthesis and also help to transport these proteins to the part known as cyton.

How does Nissl stain work?

The Nissl substance (rough endoplasmic reticulum) appears dark blue due to the staining of ribosomal RNA, giving the cytoplasm a mottled appearance. Individual granules of extra-nuclear RNA are named Nissl granules (ribosomes). DNA present in the nucleus stains a similar color.

Where the nissl’s granules are found and what is their function?

What are absent from the axon hillock and the axon?

The initial segment is the site for the initiation of the action potential. Characteristically, the axon hillock does not contain ribosomes and most of the other cell organelles. However, it does contain cytoskeletal elements or microtubular structures and organelles that move along the axon.