Скачать с ютуб How a Poison Dart Frog Kills You в хорошем качестве

How a Poison Dart Frog Kills You

#amphibians #poison #cellbio #learning Poison dart frogs are like the easter eggs of the neotropical rainforest, bright spots of color in the dense browns and greens of vegetation in various states of decay. There are close to 200 species found from Nicaragua to the southern edge of the Amazon Rainforest in Bolivia. There are quite a few relatively non-toxic species that use crypsis to avoid detection, but they are much less famous than the toxic species dressed in aposematic yellows, blues, and reds. They are called poison dart frogs because 4 species in the genus Phyllobates, which are some of the largest and most toxic in the family, are used on occasion to tip hunting blow darts, something the majority of these frogs are never used for, due to not being quite as toxic. Whether deadly or just plain unpalatable they are not born with the toxins, nor are they toxic when they first metamorphose out of the tadpole phase. The poisons are derived from their diet. They appear to sequester alkaloids invertebrates and incorporate them in their own defensive toxins. In frogs of the genus Dendrobates have skin laced with alkaloids in the pumiliotoxin family named for its presence in these amphibians, though it is derived from arthropods the frog eats. One such alkaloid is Pumiliotoxin 251D. This though is a much weaker toxin than some other dart frogs use. The Golden poison frog, which has the much less friendly sounding scientific name: Phyllobates terribilis, is one of the most toxic frogs in the world, and a single individual has enough poison to kill 10-20 people. In its cocktail of skin poisons is Batrachotoxin It irreversibly binds to sodium channels in nerve cells rendering the polar membranes non-polar. Nerve cells require polar membranes to send signals, without it the nerve cells cannot transmit information, resulting in paralysis. There is no known antidote. original footage and sound source Santos, J. C.; L. A. Coloma; D. C. Cannatella (2003). "Multiple, recurring origins of aposematism and diet specialization in poison frogs". Proceedings of the National Academy of Sciences of the United States of America. 100 (22): 12792–12797. doi:10.1073/pnas.2133521100. PMC 240697. PMID 14555763. Vandendriessche T, Abdel-Mottaleb Y, Maertens C, Cuypers E, Sudau A, Nubbemeyer U, Mebs D, Tytgat J. Modulation of voltage-gated Na+ and K+ channels by pumiliotoxin 251D: a "joint venture" alkaloid from arthropods and amphibians. Toxicon. 2008 Mar 1;51(3):334-44. PMID 18061227 "USATODAY.com - Most poisonous creature could be a mystery insect". usatoday30.usatoday.com. Retrieved 8 July 2016. John P. Dumbacher, Avit Wako, Scott R. Derrickson, Allan Samuelson, Thomas F. Spande, John W. Daly (2004): Melyrid beetles (Choresine): A putative source for the batrachotoxin alkaloids found in poison-dart frogs and toxic passerine birds. The National Academy of Sciences. Vol. 101 no. 45, 15857-15860 Wang, S. Y.; Mitchell, J.; Tikhonov, D. B.; Zhorov, B. S.; Wang, G. K. (2006). "How Batrachotoxin modifies the sodium channel permeation pathway: Computer modeling and site-directed mutagenesis". Mol. Pharmacol. 69 (3): 788–795. doi:10.1124/mol.105.018200. PMID 16354762. If you like animals and nature Please Subscribe and Like This is Backyard Expeditions. Here you can find wildlife footage and short documentaries on the natural world. Nature is full of surprises, often amazing things are happening just feet from you door. I am a biology student who was inspired by the likes of the BBC natural history unit, PBS, and animal planet as a Child. I have also long been a hobbyist photographer, filming interesting things over time. My goal is to document interesting behavior and highlight interesting species I encounter both in exotic locations, and on backyard expeditions. Underwater Worlds    • Life Underwater   Journey through the Undergrowth (Macro footage of insects and Arachnids)    • Insect and Arachnid Documentaries   Bird Playlist    • How can Woodpeckers drill wood withou...   Birding Playlist    • Плейлист   Conservation Playlist    • Fundamentals of Conservation Biology   also Check Out my Photography Adventure Blog https://johnjacksonphoto.blogspot.com/