Explain how the nettle is adapted for defence and protection

In biology, adaptation has three related meanings. The definition that relates most to this question is given below:

Adaptation is the dynamic evolutionary process that fits organisms to their environment, enhancing their evolutionary fitness.

A Nettle plant also known as common nettle, stinging nettle nettle leaf, or just a nettle or stinger, is a herbaceous perennial flowering plant in the family Urticaceae with the ability to sting.

Explanation:

One of the biological traits that the nettle has is its ability to produce inflammatory effect (that is a burning stinging sensation on the skin known as "contact urticaria"). This unpleasant effect is achieved by impaling the skin of the animal via spicules. The spicules cause mechanical irritation.

The stinging effect is also achieved by the introduction of biochemical irritants such as histamine, serotonin and choline among other chemicals into the skin.

This sort of defence or protection mechanisam keeps animals away from the nettle.

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