NEMATOCYST - SCI & TECH
News: Should
you really pee on a jellyfish sting?
What's in the news?
● Jellyfish
are gelatinous marine creatures that sting in response to pressure that
activates venom cells lining the animal's tentacles.
● These
venom cells, called nematocysts, deploy tiny, harpoon-like structures to inject
their venom into the skin and then continue to hang on like a prickly burr.
Nematocyst:
● Nematocysts
are specialized cells found in jellyfish,
corals, sea anemones and hydras, and act as potent weapons for defence and
hunting.
● Composed
of capsules containing coiled tubules and toxins, nematocysts rapidly eject
these tubules with extreme acceleration when triggered.
● Nematocysts
play a crucial role in the feeding and
defence strategies of cnidarians in particular.
● Cnidarians
are animals that contain cells called cnidocytes.
● When
potential prey comes into contact with a cnidocyte, specialized sensory
structures on the cell’s surface trigger the release of the nematocyst. The
tubule then unfurls, piercing the prey’s outer layer or injecting toxins into
its body.
Variety of Toxins:
● Toxins
within nematocysts have diverse effects: some paralyze prey, while others break
down cells.
● Cnidarians employ a
combination of toxins for effective predation or defence.
Adaptation for Survival:
● Nematocysts
complexity contributes to cnidarians success in diverse aquatic environments.
● This
adaptation makes cnidarians formidable creatures, aiding in their survival and
dominance in various ecosystems.