Final answer:
The part of a neuron that contains the nucleus and sustains the neuron's vital functions is the soma, also known as the cell body. The soma constitutes the central part of the neuron and integrates the signals received by the dendrites and transmits them down the axon to other cells.
Step-by-step explanation:
The part of a neuron that contains the nucleus and keeps the entire cell alive and functioning is the soma. The soma, or cell body, not only contains the nucleus but most of the neuron's organelles, including the mitochondria, rough and smooth endoplasmic reticulum, and Golgi apparatus. Neurons have several important structures including dendrites, which are tree-like extensions that receive messages from other neurons, and the axon, a singular long projection that transmits the electrical signal away from the soma to target cells or other neurons.
Neurons are the basic unit of communication in the nervous system, and their ability to transmit information relies on the physiological processes within these specialized cells. The transmission of a nerve impulse begins with the dendrites, which collect signals from other cells at specialized junctions known as synapses. These electrical signals are then conveyed across the soma and down the axon, ultimately reaching the terminal buttons at the axon's end, where the signal can be passed on to the next neuron or a target cell through the release of neurotransmitters.
Dendrites and axons are examples of neuron processes – extensions of the neuron's cell membrane that have specialized functions. Unlike dendrites, which mainly receive signals, the axon is responsible for propagating the nerve impulse and can branch out to communicate with multiple cells.