How is a jellyfish different from fish?

Jellyfish and fish are very different creatures, despite their similar names and aquatic habitats. Here's a breakdown of their key differences:

Jellyfish:

* Phylum: Cnidaria

* Structure: Soft-bodied, bell-shaped with tentacles. They lack a brain, bones, or a heart.

* Movement: Propel themselves by contracting their bell, which pumps water through their bodies.

* Diet: Predatory, primarily on plankton and small fish.

* Reproduction: Reproduce both sexually and asexually.

* Other: Have stinging cells (nematocysts) on their tentacles, used for defense and capturing prey.

Fish:

* Phylum: Chordata

* Structure: Have a backbone (spine), gills for breathing underwater, and fins for movement. They have a brain and a circulatory system.

* Movement: Swim using their fins and tails.

* Diet: Varied, depending on species. Can be herbivores, carnivores, or omnivores.

* Reproduction: Generally reproduce sexually by laying eggs.

* Other: Most fish have scales for protection and buoyancy.

Here's a table summarizing the differences:

| Feature | Jellyfish | Fish |

|---|---|---|

| Phylum | Cnidaria | Chordata |

| Structure | Soft-bodied, bell-shaped, no bones | Backbone, gills, fins |

| Movement | Contracting bell | Fins and tail |

| Diet | Predatory, mainly plankton | Varied (herbivores, carnivores, omnivores) |

| Reproduction | Sexual and asexual | Sexual (laying eggs) |

| Other | Stinging cells (nematocysts) | Scales for protection and buoyancy |

In essence, jellyfish are simpler organisms with a less complex body structure, while fish are more complex vertebrates with advanced physiological features.