Question

the withdrawal reflex is an example of a(n) ____________ reflex. polysynaptic contralateral inhibitory ipsilateral monosynaptic question 4 2 pts true or false: spinal nerves are mixed nerves containing both sensory and motor fibers. true false

Explanation:

• Withdrawal reflex: The withdrawal reflex is polysynaptic. In a polysynaptic reflex, there are multiple synapses (connections between neurons). The withdrawal reflex involves sensory neurons detecting a stimulus (e.g., pain), interneurons in the spinal cord, and motor neurons that cause muscle contraction to withdraw the body part. It is not monosynaptic (which has only one synapse, like the knee - jerk reflex). Contralateral refers to the opposite side (the withdrawal reflex mainly acts on the same - side/ipsilateral side initially). Inhibitory is a function (e.g., some neurons inhibit other neurons' activity), but not the main classification here. Ipsilateral is about the side (same - side), but the key classification based on the number of synapses is polysynaptic.
• Spinal nerves: Spinal nerves are indeed mixed nerves. They have dorsal roots (sensory fibers bringing information into the spinal cord) and ventral roots (motor fibers taking information out of the spinal cord to muscles and glands). So, they contain both sensory and motor fibers.

Answer:

• For the first question: polysynaptic
• For the second question: True