In relation to Big Idea 1, which is “the process of evolution drives the diversity and unity of life”, Dr. Moalem has compared the evolution of various plant toxins and its effect on the evolution of humans. From pages 79-83, he mentions many of the harmful effects some plant toxins can have on humans.
Explain using terms about evolution why plants have developed these certain toxins over time. If many toxins in plants that we regularly consume hurt us, why do we continue to breed and grow them for consumption? Should humans be able to selectively breed for plants that don’t have these toxins? Explain your answer. Pick one of the plants mentioned on pages 79-83, or one of your own, and research advantages and disadvantages that plant has for humans in consumption or usage. Then explain whether this plant is more or less beneficial to humans.
Jenny S. Li - jesli4@students.d125.org
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ReplyDeleteIn the chapter “Hey, Bud, Can You Do Me a Fava?”, Dr. Moalem describes various plants and the toxins they possess which can harm humans. The Indian vetch contains a “powerful neurotoxin that can cause paralysis” (80); nightshades contain a “large portion of alkaloids” (80); raw habanero peppers contain a “chemical called capsaicin” (82). The different toxins the plants produce are related to Big Idea 1. Through the process of evolution there is diversity within plants and how they interact with their environment. This begins with variations within plants which can rise due to random mutations within the genetic code of the plants or through random fertilization. The environment then adds selective pressures on the plants such as an increase in a type of predator or a change in weather. Those plants possessing favorable traits are able to survive and reproduce while those that are selected against will have a much lower chance of survival. Over a period of time the population of plants will have adapted and the change in allele frequency within a population is called microevolution. Over a much longer period of time and with the aid of isolating factors such as geographic barriers, macroevolution and speciation will occur.
ReplyDeleteSure some plant toxins may “paralyze, sterilize, or make us crazy” but it doesn’t change the fact that humans are still cultivating and consuming plants because they possess health benefits. An example of this is the Apple of Sodom which is a species of poisonous plant which bear tomato-like fruit. Tea from this plant stimulate appetite and help the liver and spleen. This plant also helps with digestive problems and can also be used to treat skin infections such as acne. Although certain plant toxins possess negative side effects on the human body, these poisonous plants are still cultivated because they do possess advantages that can help our systems. Humans should be able to selectively breed plants without toxins because for certain plants, it is not necessarily the toxins within the plants that our bodies need or want but other parts of the plants such as the stem or bark of plants that can be used for respiratory infections without having to tap into the toxins. By selectively breeding for non-toxic plants, humans can reap the advantages these poisonous plants have to offer without fear of a potential large side effect from the toxins.
Focusing on nightshades, some are edible while others can be poisonous for animals and humans. Examples of the edibles can be found right in your very kitchen such as tomatoes, potatoes, and eggplants. A primary kind of alkaloid or chemical produced by the plant that can be harmful is solanine. Too much consumption of solanine can lead to an interference with the production of enzymes in muscle tissues and can also cause inflammation. As we’ve learned in previous units enzymes are necessary in order to continue metabolic functions within our bodies. However, in small dosages these alkaloids can be protective. In tomatoes for example, the alkaloid lycopene has been shown to prevent osteoporosis as well as cancer. With this nightshades can be beneficial to humans but too much of the toxins some of these plants can produce can lead to harm for humans. In the end, it depends on the dosage and how much of these toxins we’re ingesting. If the proper amounts are consumed, then these plants labeled poisonous can in fact help humans more than harm them.
Faith Teodoro (fteodor4@students.d125.org)
Sources:
(http://www.bukisa.com/articles/103380_commercial-health-and-medicinal-benefits-from-poisonous-plants)
(http://sacredsourcenutrition.com/nightshades-to-eat-or-not-to-eat/)