Final answer:
The phrenic nerve controls diaphragm movement and is located in the cervical plexus. The sciatic nerve is responsible for lower limb sensation and comes from the sacral plexus.
Step-by-step explanation:
The phrenic nerve is responsible for diaphragm movement, which controls breathing. It is a systemic nerve located in the cervical plexus. On the other hand, the sciatic nerve is primarily associated with lower limb sensation. It is a combination of the tibial nerve and the fibular nerve and originates from the sacral plexus.
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