Question

Which animal has no heart and brain?

Answer 1

Jellyfish:

1. The informal popular names for the medusa-phase of several gelatinous members of the subphylum Medusozoa, a significant division of the phylum Cnidaria, are jellyfish and sea jellies.
2. Although jellyfish have no hearts, they can get rather big even brains.
3. At the base of their tentacles, they have a basic collection of nerves that can sense touch, temperature, salinity, and other things.
4. They rely on automatic reflexes to react to these stimuli because they lack a brain.
5. They don't need lungs since their skin is so thin that they can absorb oxygen through it.
6. They don't need the heart to pump blood because they don't have any.