How do Stinging Nettles Inject Poison? —Kaare Jensen

<p>The leaves of stinging nettles are covered in 'pipette-like' stingers which penetrate the skin on contact and deposit a small amount of poison. The 'pipette-like' design means that almost all of the poison contained in the stinger can be injected at once if sufficient force is applied to bend the stinger to an angle of 90 degrees. This is demonstrated in laboratory experiments conducted by Kaare Jensen at the Technical University of Denmark.</p>