Final answer:
The spinothalamic tract is responsible for transmitting pain and temperature sensations and crosses the midline in the spinal cord, while the dorsal column system is in charge of touch and proprioception and decussates in the medulla.
Step-by-step explanation:
The spinothalamic tract and the dorsal column system are two major ascending pathways in the spinal cord, each responsible for relaying different types of sensory information to the brain. The spinothalamic tract primarily conveys pain and temperature sensations. This tract decussates (crosses over) in the spinal cord soon after the sensory information enters, meaning the pain and temperature sensations from one side of the body are processed by the opposite side of the brain. In contrast, the dorsal column system carries information about touch and proprioception, crossing over in the medulla.
Both of these pathways originate from sensory neurons in the dorsal root ganglia and are vital for our perception of different stimuli. They help us respond to various sensory inputs by providing detailed and localized information about the stimuli, such as the intensity and location of pain, which can lead to a sense of shock when it occurs. The trigeminal nerve contributes similar information from the face and head regions into these pathways.