Final answer:
The cell body (or soma) of a mature neuron usually contains centrioles, mitochondria, synaptic vesicles, and rough endoplasmic reticulum.
Step-by-step explanation:
The cell body (or soma) of a mature neuron typically contains several organelles, including centrioles, mitochondria, synaptic vesicles, and rough endoplasmic reticulum.
Centrioles are involved in cell division and are found in most animal cells, including neurons. Mitochondria are responsible for producing energy for the cell through cellular respiration. Synaptic vesicles store and release neurotransmitters that allow for communication between neurons. Rough endoplasmic reticulum is involved in protein synthesis. These organelles play important roles in the functioning of a neuron and support its various activities.