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Everyone knows that if one were to grab nettle with a bare hand, he would experience a painful, burning sensation.

Tiny stinging hairs with biologically active substances grow on the stem and the leaves of nettle. When they come into contact with the skin, the sharp tips of the hairs pierce its upper layers, and the substances are injected into the organism. These substances cause rash and irritation, which have to do with the impact of the substances on the blood vessels (their inflation causes the redness) and on the nerve endings. In this way, nettle protects itself from animals that might harm it.

Press "Run" button to initiate the animation. Press "Stop" to bring it to a halt, and press "Reset" to return the model to its initial state.

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