Polyribosomes - there are several free ribosomes attached by a thread. The associated ribosomes work on it to make multiple copies of the same protein. Neurons need an enormous amount of energy. The brain is one of the most metabolically active tissues in the body. In man, for example, the brain uses 40 ml of oxygen per minute.
Mitochondria use oxygen and glucose to produce most of the cell's energy.
The chemical energy stored in ATP is used to fuel most of the biochemical reactions of the neuron. For example, special proteins in the neuronal membrane use the energy released by the breakdown of ATP into ADP to pump certain substances across the membrane to establish concentration differences between the inside of the neuron and the outside. A system of tubes for the transportation of materials within the cytoplasm. With ribosomes, the ER is important for protein synthesis. Nissl Bodies - Groups of ribosomes used for protein synthesis.