Capsule

Each nematocyst contains a shot of venom comprised of proteins that can enter and damage cells, and a range of neurotoxins. The specific formula varies across species, which is why some jellyfish are much deadlier than others.

Nematocyst

Inside the nematocyte is a toxin-bearing organelle composed of several parts, all of which are ejected at high speed when activated. It is sometimes known as the ‘stinging organ’.

Cnidocil

These sensory receptors sit on the surface and are primed to detect various stimuli, including movement, certain chemicals or a change in temperature.

Nematocyte

A jellyfish’s tentacles – and sometimes its entire body – are lined with stinging cells that are used to both attack prey and defend against predators.

Tubule

A thread-like coiled tube attached to the dart unfurls to deliver the venom.

Dart

 A mini harpoon punctures the epidermis of the victim like a needle during an injection. Small barbs ensure it locks into place after piercing the skin.

Operculum 

The top of the nematocyte is covered by a trapdoor-like lid that springs open when a life form has been detected.