Question

Nissl bodies are mainly composed of
A) Nucleic acid and SER
B) Proteins and lipids
C) Free ribosomes and RER
D) DNA and RNA

Answer 1

Hint:Nissl bodies are large granular bodies which are present in the neurons and they are made up of Rough Endoplasmic Reticulum (RER).

Complete answer:
Let us first know more about nerves. Nerves are the fundamental unit of the nervous system. The nerve is made up of different parts,
Nerve cell body - It consists of eukaryotic cell components like nucleus and cell organelles
Axon - It is a long and thin fibre which extends from cell body and branches at its tips
Dendrites - The tiny projections which are found branching out the neurons receiving end
Nissl bodies are also known as nissl granules or nissl substances are found in the nerve cell body of the neurons. They are made up of free ribosomes and ROugh Endoplasmic Reticulum (RER). Therefore, this is the correct option.
Their main function is to synthesize and release proteins which are required for neuronal growth and also regeneration of axons.

As nissl bodies are made of free ribosomes and RER, therefore, all the other options are incorrect.

Thus, the correct option is (C) free ribosomes and RER.

Note: Let us look into the various functions of neurons,
>They help in transmission of information from one nerve cell to another nerve cell.
>They can transfer information from one nerve cell to another muscle or gland cells too.
>They receive signals from the brain and transmit it to the other neurons.
>They help in electrical and chemical synapse.