GFP

The GFP (Green Fluorescent Protein) exhibits bright green fluorescence when exposed to blue light. Although many other marine organisms have similar green fluorescent proteins, GFP traditionally refers to the protein first isolated from the jellyfish Aequorea victoria. Although it has been used by artists around the world, this GFP is especially useful for the biological sciences. In biology, GFP is used for highlighting specific structures. Compared to other fluorescent proteins, it is much less harmful when illuminated in living cells. The discovery and use of GFP has triggered the development of highly automated live-cell fluorescence microscopy systems, which can be used to observe cells over time expressing one or more proteins tagged with fluorescent proteins. In 2008 Martin Chalfie, Osamu Shimomura, and Roger Y. Tsien were awarded the Nobel Prize in Chemistry for their discovery and development of the green fluorescent protein.

 Wiki - Green Fluorescent Protein

The immortal jellyfish

The lifecycle of the jellyfish is quite remarkable (pictured below). A jellyfish larva first develops into a polyp and it is this polyp that will then asexually produce thousands of jellyfish. This surely is rather bizarre but thanks to Turritopsis nutricula, this lifecycle gets a whole lot weirder.

Turritopsis nutricula is potentially immortal, it is a hydrozoan whose medusa, or jellyfish, form can revert back to the polyp stage after becoming sexually mature. It is the only known case of a metazoan capable of reverting completely to a sexually immature, colonial stage after having reached sexual maturity as a solitary stage. It does this through the cell development process of transdifferentiation. Cell transdifferentiation is when the jellyfish "alters the differentiated state of the cell and transforms it into a new cell". In this process the medusa of the immortal jellyfish is transformed into the polyps of a new polyp colony. First, the umbrella reverts itself and then the tentacles and mesoglea get resorbed. The reverted medusa then attaches itself to the substrate by the end that had been at the opposite end of the umbrella and starts giving rise to new polyps to form the new colony. Theoretically, this process can go on indefinitely, effectively rendering the jellyfish biologically immortal.