Jellyfish are free-swimming marine animals, characterised by their gelatinous dome with trailing curtain of tentacles. They swim by sending pulses through the dome, propelling them forward. Jellyfish are ancient and primitive creatures, lacking in a respirative system. Their body is thin enough to oxygenate via diffusion - allowing them to absorb oxygen directly from the water. The tentacles are equipped with stingers to help them catch and stun prey. If food is adequate, they will spawn daily, with individuals simultaneously releasing their eggs or sperm into the water. They can also reproduce asexually by budding.