Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!ucbvax!ucsd!rutgers!sunybcs!kitty!larry From: larry@kitty.UUCP (Larry Lippman) Newsgroups: sci.bio Subject: Re: Plant Hormones Summary: Various naturally occuring substances... Message-ID: <3130@kitty.UUCP> Date: 30 Apr 89 05:04:00 GMT References: <17728@cup.portal.com> Organization: Recognition Research Corp., Clarence, NY Lines: 38 In article <17728@cup.portal.com>, mmm@cup.portal.com (Mark Robert Thorson) writes: > When I was in school, there were only five known plant hormones. I can only > remember four: 1) florigen, which had been shown to exist through > experiment, 2) kinetin, which also was only known through its effect, but > was believed to consist of RNA fragments, 3) auxin, which was known through > experiment and through discovery of synthetic auxins, and 4) FRH (fruit > ripening hormone) which was the only hormone whose chemical structure was > known (it is the 6-atom molecule ethylene). > > Can someone update me on plant hormones? How many are known to exist? > If the list is short, please describe their name, chemical structure, > and effects. I'm not big on plants, but I'll see what I can remember... The first plant growth hormone that comes to mind is 3-indoleacetic acid. This is one variety of auxin, but there are other auxins. This substance is not unique to plants; it is also found in urine. Another plant growth hormone is gibberellin. A particular variety of gibberellin is - what else? - gibberellic acid. Another plant growth hormone is 6-furfurylaminopurine, which is also known as cytokinin or kinetin. Another plant growth hormone is abscisic acid, which is a type of pentadienoic acid. I have never heard of FRH (FSH, though :-) ) or florigen. All of the above plant growth hormones have different mechanisms of action; i.e., some stimulate roots, others leafs and stems, etc. I don't remember which hormone does what except that cytokinin definitely stimulates mitosis in both plant and animal cells. <> Larry Lippman @ Recognition Research Corp. - Uniquex Corp. - Viatran Corp. <> UUCP: {allegra|ames|boulder|decvax|rutgers|watmath}!sunybcs!kitty!larry <> VOICE: 716/688-1231, 716/773-1700 {att|hplabs|utzoo}!/ <> FAX: 716/741-9635, 716/773-2488 "Have you hugged your cat today?"