I believe that it is because when you put the hand on ice it causes the hand too cool and prevents/slows the rate at which the nerves get damaged.
Answer:
The first line of defence (or outside defence system) includes physical and chemical barriers that are always ready and prepared to defend the body from infection. These include your skin, tears, mucus, cilia, stomach acid, urine flow, 'friendly' bacteria and white blood cells called neutrophils.
Explanation:
