Final answer:
The axon terminal is enlarged into a knoblike structure called a synaptic end bulb, which is essential for neurotransmitter release and signal transmission in the nervous system.
Step-by-step explanation:
The axon terminal is enlarged into a knoblike structure called a synaptic end bulb. This structure is crucial for the transmission of signals in the nervous system. When an action potential reaches the axon terminal, the synaptic end bulb releases neurotransmitter molecules onto a target cell across a synapse. The release of neurotransmitters facilitates the communication of signals to other neurons, muscle cells, or glands, thus allowing for the proper functioning of the nervous system.
An axon is an extension of a neuron which transmits electrical impulses away from the neuron's cell body. The axoplasm is the cytoplasm within the axon and has a distinct composition compared to the cell body. Moreover, axon terminals often have several branches extending towards the target cell, which is pivotal in the signal transmission process.
Neurons typically have one or two axons, and these axons can be covered by a myelin sheath, which aids in increasing the speed of electrical signal conduction. Notably, the myelin sheath is produced by glial cells, not neurons themselves, and there are periodic gaps in the myelin known as nodes of Ranvier.