Thursday, August 4, 2016

Planarian: "effectively immortal" science model for regeneration and aging research


Planaria are common to many parts of the world, living in both saltwater and freshwater ponds and rivers. Some species are terrestrial and are found under logs, in or on soil. Others can be found on plants in humid areas.They play an important role in watercourse ecosystems and are often very important as bio-indicators.

Planaria have a solid body with no body cavity. The blunt, triangular head has two eye-spots, pigmented areas that are sensitive to light. There are two earlike projections at the base of the head, which are sensitive to touch and the presence of certain chemicals. They have single-opening digestive tract. Planaria eat living or dead small animals that they suck up with their muscular mouths. Planaria receive oxygen and release carbon dioxide by diffusion through the body wall.

There are sexual and asexual planaria. Sexual planaria are hermaphrodites, possessing both testicles and ovaries. Asexual planaria detaches its tail and each half regrows the lost parts by regeneration resulting in two worms.

Planaria can be cut into pieces, and each piece can regenerate into a complete organism. A piece of planaria, estimated to be as little as 1/279th of the organism, can regenerate into a complete organism over the course of a few weeks. The organism itself does not have to be completely cut into separate pieces for the regeneration phenomenon. If the head of a planarian is cut in half down its center, and each side retained on the organism, it's possible for the planaria to regenerate two heads and continue to live.

Tal Shomrat and Michal Levin have shown that planaria exhibit evidence of long-term memory retrieval after regenerating a new head.

Recent genetic screens have uncovered 240 genes that affect regeneration. Many of these genes have orthologs in the human genome. Planarian have a number of cell types, tissues and simple organs that are homologous to our own cells, and organs. Planarian have an apparently limitless regenerative capacity, and asexual animals seem to maintain their telomerase levels throughout their lifetime making them "effectively immortal".

Nature has answers to our questions about regeneration, aging and immortality. Feel free to use the knowledge!
Have fun and happy bug hunting :)


  1. Achieving Immortality? - No problem at all! - I can make everybody Immortal in less than a month - We humans can stop aging (by wiping out all diseases) and live forever (like our creators from the planet of Nibiru - The Anunnaki) - I got the key to our Biological Immortality - By staying absolutely healthy all the time - By doing my discovery (just an exercise for a minute a day) - My WVCD - The Weapon of Virus and Cancer Destruction, that cures and prevents any diseases, known on Earth for millions of years, even radiation disease (concerning space flights) - I will describe my WVCD to everyone, who sends me a check for one million bucks - Everybody will stay absolutely healthy all the time, living their Endless Lives, for Infinite Health = Immortality.

    1. Achieving immortality is not a problem! All mortal have little mortal problems. All big immortal problems starts once you become immortal - do you have cure for that :)