Second Draft edit

Plants possess a pigment called phytochrome. Phytochrome comes in two forms: pr and pfr. Red light (which is present during the day) converts phytochrome to it's active form (pfr). This then triggers the plant to grow. In turn, far-red light is present in the shade or in the dark and this converts phytochrome from pfr to pr. Pr is the inactive form of phytochrome and will not allow for plant growth. This system of pfr to pr conversion allows the plant to sense when it is night and when it is day.[1] Pfr can also be convereted back to Pr by a process known as dark reversion, where long periods of darkness trigger the conversion of Pfr. [2]This is important in regards to plant flowering. Experiments by Halliday et. al showed that manipulations of the red-to far-red ratio in Arabidopsis can alter flowering. They discovered that plants tend to flower later when exposed to more red light, proving that red light is inhibitory to flowering. [3] Other experiments have proven this by exposing plants to extra red-light in the middle of the night. A short-day plant will not flower if light is turned on for a few minutes in the middle of the night and a long-day plant can flower if exposed to more red-light in the middle of the night. [4]

Cryptochromes are another type of photoreceptor that is important in photoperiodism. Cryptochromes absorb blue light and UV-A. Cryptochromes entrain the circadian clock to light. [5] It has been found that both cryptochrome and phytochrome abundance relies on light and the amount of cryptochrome can change depending on day-length. This shows how important both of the photoreceptors are in regards to determining day-length. [6]


FIRST DRAFT edit

Sources:

Chamovitz, Daniel (2013). What a Plant Knows. New York: Scientific American. ISBN 978-0-374-28873-0

Boundless. "The Phytochrome System and Red Light Response." Boundless Biology Boundless, 26 May. 2016.

WITHROW, R. B.  Photoperiodism and related phenomena in plants and animals. 1959 pp.xvii + 903 pp

H. A. BORTHWICK, S. B. HENDRICKS Photoperiodism in Plants. SCIENCE28 OCT 1960 : 1223-1228

Bäurle, Isabel et al. The Timing of Developmental Transitions in Plants. Cell , Volume 125 , Issue 4 , 655 - 664

How different types of light affect plants:

Plants possess a pigment called phytochrome. Phytochrome comes in two forms: pr and pfr. Red light (which is present during the day) converts phytochrome to it's active form (pfr). This then triggers the plant to grow. In turn, far-red light is present in the shade or in the dark and this converts phytochrome from pfr to pr. Pr is the inactive form of phytochrome and will not allow for plant growth. This system of pfr to pr conversion allows the plant to sense when it is night and when it is day.[1] It has been recently discovered that plants sense the amount of darkness rather than light to determine when to perform physiological functions such as flowering. [4]There are short-day and long-day plants. Short-day plants flower when there is more darkness during a 24-hour period than light. Long-day plants are the opposite. They will flower when there is a longer period of light during the day, like in the summer. These long-day and short day plants can be manipulated into flowering by exposing plants to extra red-light in the middle of the night. A short-day plant will not flower if light is turned on for a few minutes in the middle of the night and a long-day plant can flower if exposed to more red-light in the middle of the night. [4]

IDEA DRAFT edit

  • Potential topic 1:
    • Plants in space - This article provides a list of experiments for growing plants in space but does not provide specific examples of the experiment or what was found about growing plants in space. I think that it will be interesting to do research on what was found about the physiology of plants by growing them in space.
        • For example: Allan H. Brown wanted to test if certain plant behaviors and movements still existed in space. Aboard the space shuttle Columbia in 1983 sunflower seedling movements were monitored while in orbit and almost all of the seedlings still experienced rotational growth in the lack of gravity, showing that circumnutation is a built in plant behavior. [7]

Many of the things cited in the "plants grown in space" section and the "experiments in space section" link to general wikipedia pages that don't really give any information on that particular plant or experiment in space. I think a lot more research can be done to expand this page and show key experiments and how they contribute to our current understanding of plant physiology.

I do think that this article does a fine job at including relevant information and not adding anything distracting, but i do think more can be added. This article doesn't seem to take any sides or try to sway the reader in a particular direction.

Although, a lot of their sources come from nasa, so i am worried that some information might be excluded due to an accidental bias from the NASA sources. I think that more primary articles should be read for more information on the physiology aspect. Not all of their sources have links, but many do which I think is good for the reader to be able to get more info if needed. There was a large section under the talk page about "Tomatosphere Research" which is confusing as to why it is not in the article. There is also no name or anything associated with this information.

  • Potential topic 2:
    • Photoperiodism- This article starts to discuss how photoperiodism works in plants with long day and short day plants but it doesn't discuss how the different types of light play a role. It is also not mentioned how exactly scientists discovered that it was night length instead of day length. A possible edit could be:
        • Scientists discovered that it was not the length of day that determines whether or not a plant flowers but instead it was the amount of darkness. Short-day plants such as soybeans and be manipulated into not flowering simply by turning the lights on for a few minutes in the middle of the night. The same can be done for long-day plants like the iris. If the lights are turned on for a few minutes in the middle of the night it can induce flowering even in the middle of winter. [4]
        • Most of the sources on this article come from primary research, which is a good thing. Although not in the scope of this class, I do want to note that the animal section of this article is lacking many citations. I think that this article is very neutral and represents all view points. I do think that more work can and should be done on day-neutral plants. there is a little info on long and short day plants and barely any on the day neutral ones. The talk page for this article has more discussion than any article I have seen so far. I think that this really shows how helpful talk pages are, because it is discussed between multiple people what should be done to improve the page- in this case it was many formatting things but there were also questions that people had asked that were answered by others.

I do think that this article needs to add more citations as every fact is not followed by a citation. I think this topic will help with my own understanding of how red, far-red and blue light play a role in photoperiodism.

ARTICLE EVALUATIONS edit

BOTANY ARTCILE

  • Is everything in the article relevant to the article topic? Is there anything that distracted you?
    • "A botanist or plant scientist is a scientist who specialises in this field.The term "botany" comes from the Ancient Greek word βοτάνη (botanē) meaning "pasture", "grass", or "fodder"; βοτάνη is in turn derived from βόσκειν (boskein), "to feed" or "to graze". " I did not think that this was necessary.
    • "The study of plants is vital because they underpin almost all animal life on Earth by generating a large proportion of the oxygen and food that provide humans and other organisms with aerobic respiration with the chemical energy they need to exist." This sentence does not really make sense to me.
  • Is the article neutral? Are there any claims, or frames, that appear heavily biased toward a particular position?
    • I think the editor(s) of this article are heavily biased towards plants( not that that's a bad thing!). But I get the impression that they believe that plants are the most important organisms on earth.
  • Are there viewpoints that are overrepresented, or underrepresented?
    • I don't necessarily think there are view points that are underrepresented. You can't really write an article on botany without explaining the complexity of plants. But I do think they could have been a little more neutral instead of trying to convince the reader how great plants are.
  • Check a few citations. Do the links work? Does the source support the claims in the article?
    • Not all of the links work. Also some links under the reference category take you to the end of the article where it is cited again and you have to click on it there. I just found this a little annoying. I also felt like things that were hyperlinked to another wikipedia page did not necessarily need to be hyperlinked like: seed.
  •  Is each fact referenced with an appropriate, reliable reference? Where does the information come from? Are these neutral sources? If biased, is that bias noted? 
    • As i said before, there is almost too much citation. All of their references at the end did seem like they were reliable scientific articles.
  • Is any information out of date? Is anything missing that could be added?
    • I would have liked to see innovations made in modern day botany. They discussed a lot of history of botany but didn't really dive into what current botanists are doing (besides medicine). Plants can be used for a lot of stuff and we have definitely made some innovations recently.
  •  Check out the Talk page of the article. What kinds of conversations, if any, are going on behind the scenes about how to represent this topic? 
    • Any talk going on is about fixing an external link. There is not much talk about the content of the article.
  • How is the article rated? Is it a part of any WikiProjects?
    • GA class (meaning it is complete but can be made better). and a level 3 vital article. Part of WikiProject Plants, WikiProject Biology, WikiProject Horticulture and Gardening.
  • How does the way Wikipedia discusses this topic differ from the way we've talked about it in class?
    • I felt that the grammar was very bad in this article. They talked a lot about the history and then biochemistry, which are not really areas we have discussed in class.

PLANT PHYSIOLOGY ARTICLE

  • Is everything in the article relevant to the article topic? Is there anything that distracted you?
  • Is the article neutral? Are there any claims, or frames, that appear heavily biased toward a particular position?
    • I think that this article is pretty neutral. i don't think that it is particularly trying to sway the reader in any direction (I don't even know what direction it would be!)
  • Are there viewpoints that are overrepresented, or underrepresented?
    • I do not think there was any particular view point represented at all.
  • Check a few citations. Do the links work? Does the source support the claims in the article?
    • The citations on this article are awful (in the reference section). Some do not have links and the ones that do, link to a page that is of no relevance.
  •  Is each fact referenced with an appropriate, reliable reference? Where does the information come from? Are these neutral sources? If biased, is that bias noted? 
    • I do think that many facts need more citations. I think that a lot of the information provided comes from other wikipedia articles, instead of peer-reviewed research papers which will provide the most information.
  • Is any information out of date? Is anything missing that could be added?
    • I think there is SO much current research going on in plant physiology that could have been mentioned, instead of a couple lines like in this article. I think there is a lot that we don't know that could have been discussed.
  •  Check out the Talk page of the article. What kinds of conversations, if any, are going on behind the scenes about how to represent this topic? 
    • There is only one question in the talk section that is asking about surface tension. I think if the talk section was utilized more it could help people edit the article.
  • How is the article rated? Is it a part of any WikiProjects?
    • This article is rated as a B class and is part of WikiProjects plants.
  • How does the way Wikipedia discusses this topic differ from the way we've talked about it in class?
    • I think in class we talk about physiology of plant behavior, not physiology of plants. Granted, we all took bio 220 and know the basics, i think that we are not as concerned with all of the interior processes of the plant but how they communicate with others and respond to environmental stimuli.
  1. ^ a b Fankhauser, Christain (February 16, 2001). "The Phytochromes, a Family of Red/Far-red Absorbing Photoreceptors". Journal of Biological Chemistry. 276: 11453–11456.
  2. ^ Casal, J.J. (2014). "Light perception and signalling by phytochrome A". Journal of Experimental Botany. 65 (11).: 2835–2845.
  3. ^ Lin, Chentao (2000). "Photoreceptors and Regulation of Flowering Time". Plant Physiology. 123: 39–50.
  4. ^ a b c d Chamovitz, Daniel (2013). What A Plant Knows. New York: Scientific American. pp. 17–18. ISBN 978-0-374-28873-0.
  5. ^ Lin, Chentao (2005). "The cryptochromes". BioMed Central: Genome Biology. 6:220.
  6. ^ Mockler, Todd (2003). "Regulation of photoperiodic flowering by Arabidopsis photoreceptors". Proceedings of the National Academy of Sciences of the United States of America. 100 (4): 2140–2145.
  7. ^ Chamovitz, Daniel (2013). What A Plant Knows. New York: Scientific American. pp. 109–110. ISBN 978-0-374-28873-0.