Final answer:
The spinothalamic tract is a major sensory pathway that carries pain and temperature sensation from the body to the brain. It consists of three successive neurons that transmit the sensory signals. The tract synapses in the postcentral gyrus of the cerebral cortex.
Step-by-step explanation:
The spinothalamic tract is a major sensory pathway in the spinal cord that carries information about pain and temperature sensation from the body to the brain. It consists of three successive neurons that work together to transmit the sensory signals. The first neuron starts in the dorsal root ganglion, extends its axon to the dorsal horn, and synapses with the second neuron. The second neuron has its cell body in the gray matter of the spinal cord and connects to the thalamus. Axons from the second neuron decussate within the spinal cord and ascend to the brain, where they synapse with the third neuron in the thalamus. Finally, the third neuron projects its axon to the spinothalamic tract, which synapses in the postcentral gyrus of the cerebral cortex.