Question

which kind of er is associated with protein synthesis and why ?

Answer 1

There are two types of endoplasmic reticulum, rough and smooth. The outer (cytosolic) face of the rough endoplasmic reticulum is studded with ribosomes that are the sites of protein synthesis. The rough endoplasmic reticulum is especially prominent in cells such as hepatocytes.

Answer 2

As the nitrogen is the importent element which used in the synthesisis of protein and other compound. This is taken up in the form of inorganic nitrated and nitrites and in organic compound which have been prepared by bacteria from atmospheric nitrogen