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Speaker 1: Welcome to Brainstuff from house Stop works dot com where

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Speaker 1: smart happens. Hi Am Marshall Brain with today's question, how

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Speaker 1: does the herbicide round up work? Round Up, which is

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Speaker 1: a trade name used by Monsanto, and other herbicides based

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Speaker 1: on glyphosphate, which is the generic name, are probably the

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Speaker 1: most commonly applied weed killers in use today. These herbicides

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Speaker 1: are used by everyone from farmers to foresters, to gardeners

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Speaker 1: to biologists who are trying to control invasive exotic plants.

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Speaker 1: Glyphosphate based herbicides all work on the same biochemical principle.

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Speaker 1: They inhibit a specific enzyme that plants need in order

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Speaker 1: to grow. The specific enzyme is called EPSP synthase. Without

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Speaker 1: that enzyme, plants are unable to produce other proteins essential

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Speaker 1: to growth, so they yellow and dye over the course

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Speaker 1: of several days or weeks. Majority of plants use this

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Speaker 1: same enzymes, so almost all plants to come to round up.

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Speaker 1: If you've read the How Stuff Works article called how

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Speaker 1: Cells Work, you know a good bit about DNA and

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Speaker 1: how it produces enzymes in the same way that many

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Speaker 1: antibiotics gum up enzyme production to kill bacteria. Glyphosphate gums

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Speaker 1: up enzymes and plants to kill them. Glyphosphate kills plants

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Speaker 1: like antibiotics kill bacteria. If you've been following farming news

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Speaker 1: or the genetically modified food debate, you know that glyphosphate

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Speaker 1: tolerance seeds are now available. You can buy genetically modified corn, soybeans,

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Speaker 1: and so on that are immune to glyphosphate. These plants

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Speaker 1: use an enzyme that performs the same function as EPSP synthas,

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Speaker 1: but is not inhibited by glyphosphate. Round up will kill

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Speaker 1: almost any plant, including aquatic plants, so you want to

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Speaker 1: be sure to avoid spray drift onto other plants or

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Speaker 1: into the water. Any pesticide should be applied carefully. Do

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Speaker 1: you have any ideas or suggestions for this podcast? If so,

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Speaker 1: please send me an email at podcast at how stuff

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Speaker 1: works dot com. For more on this and thousands of

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Speaker 1: other topics, go to how stuff works dot com and

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Speaker 1: be sure to check out the brain stuff blog on

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Speaker 1: the how stuff works dot com home page.