Answer:
The nerves in the integumentary system (skin) sense the irritation and send the signal to the brain. The brain then sends impulses through the nervous system to scratch the itch.
Explanation:i hope this helps u :)
Longest to Shortest:
<span>across the diameter of the galactic halo - 200,000 light years
</span><span>across the diameter of the galactic disk - 100,000 light years
</span><span>from the sun to the center of the galaxy - 26,000 light years
</span><span>across the diameter of the central buldge - 20,000 light years
</span><span>through the disk from top to bottom - 1,000 light years.</span>
