Article Evaluation edit

Botany

  • This is a mostly complete, well written article that has been rated GA by a number of reviewers, which is the third best rating.
    • GA stands for good article and means that it is useful for nearly all readers but would benefit from further fine tuning.
  • There are still a number a paragraphs without proper citations, according to the tutorial.
  • All of the bibliography links I tried worked.
  • To me, the article seems to be a non biased presentation of the subject.
  • In the talk page, someone recommended linking some of the complex sub topics to shorten the article for people more looking for a general overview. This is an interesting thought, and I wonder what the consensus is among wikipedians. I agree for the most part, and think that for many people a smaller, more concise article is easier to manage and as long as there are plenty of links they can explore further as they please.

Plant Physiology

  • No citations in the entire "aims" section, leaving me to wonder where the authors obtained that information and whether it may be merely their opinion.
    • Each paragraph should have a citation whether there is a quote or not.
    • Much of the article is not cited at all.
  • Overall the article seems to be written in a non biased way, and is a good overview of the topic.
  • In my opinion, it doesn't need to be much more detailed since each section has plenty of links to separate articles on the sub topics.
  • People have commented in the talk section that more citations are needed, along with adding graphs from famous experiments and expanding on the economic importance section.
  • The article has been rated B-class by the WikiProject Plants group and as C-class by the Version 1.0 Editorial Team.

Ideas Draft edit

Article 1. Hedera helix

  • a lot of research has been done on the mechanism of adhesion for English Ivy
  • while the article is sufficient on a basic level, it would be interesting to add a section on the secretions made and how their composition is being studied for use as an adhesive

Add new section:

Mechanism of Adhesion

Hedera helix uses adhesive disks on the tips of its adventitious roots to adhere to smooth vertical surfaces. These disks secrete nanoparticles that are capable of producing a force 1.8 million times the weight of the disk. [1]

Article 2. Trichome

  • this article is a good start, but is missing citations and could be much more detailed
  • in the talk section, someone mentioned that trichomes are generally grouped into glandular, non glandular, and stinging trichomes
  • I am most interested in researching glandular trichomes and the various chemical compounds plants secrete through them for defense
  • Plants may use trichomes in order to deter herbivore attacks via physical and/or chemical means, e.g. in specialized, stinging hairs of Urtica (Nettle) species that deliver inflammatory chemicals such as histamine. Glandular trichomes contain compounds including terpenes, phenolics, and alkaloids that are toxic to certain plant pests. Non glandular trichomes provide a physical barrier around the leaf, making it very difficult for insects to move through the dense hairs. [2]Studies on trichomes have been focused towards crop protection, which is the result of deterring herbivores (Brookes et. al 2016). However, some organisms have developed mechanisms to resist the effects of trichomes. The larvae of Heliconius charithonia, for example, are able to physically free themselves from trichomes, are able to bite off trichomes, and are able to form silk blankets in order to navigate the leaves better.

First Draft edit

Hedera helix

Mechanism of Attachment

Hedera helix is able to climb relatively smooth vertical surfaces, creating a long lasting adhesion of impressive strength. This is accomplished through a complex method of attachment in which adventitious roots growing along the stem make contact with the surface and extend root hairs. These tiny hairs grow into any small crevices available, secrete glue-like nanoparticles, and lignify.[3] This glue-like substance is a nanocomposite adhesive that consists of uniform nanoparticles 50-80 cm in diameter in a liquid polymer matrix. Cross linking reactions occur between these components, creating a remarkably strong adhesion. Chemical analyses of the nanoparticles detected only trace amounts of metals, once thought be responsible for their high strength, indicating that they are largely organic. Recent work has shown that the nanoparticles are likely composed of arabinogalactan proteins (AGPs).[4][5]

Second Draft edit

Hedera helix edit

Mechanism of Attachment edit

Hedera helix is able to climb relatively smooth vertical surfaces, creating a strong, long lasting adhesion with a force of around 300 nN.[6] This is accomplished through a complex method of attachment starting as adventitious roots growing along the stem make contact with the surface and extend root hairs that range from 20-400 μm in length. These tiny hairs grow into any small crevices available, secrete glue-like nanoparticles, and lignify. As they dry out, the hairs shrink and curl, effectively pulling the root closer to the surface.[3]The glue-like substance is a nano composite adhesive that consists of uniform spherical nanoparticles 50-80 nm in diameter in a liquid polymer matrix. Chemical analyses of the nanoparticles detected only trace amounts of metals, once thought be responsible for their high strength, indicating that they are largely organic. Recent work has shown that the nanoparticles are likely composed in large part of arabinogalactan proteins (AGPs), which exist in other plant adhesives as well.[4][5]The matrix portion of the composite is made of pectic polysaccharides. Calcium ions present in the matrix induce interactions between carboxyl groups of these components, causing a cross linking that hardens the adhesive.[4]

  1. ^ Zhang, Mingjun (January 2010). "Adhesion Mechanics of Ivy Nanoparticles". Journal of Colloid and Interface Science. 344: 533–540.
  2. ^ Levin, Donald A. (March 1973). "The Role of Trichomes in Plant Defense". The Quarterly Review of Biology. 48: 3–15.
  3. ^ a b Melzer, Bjorn (September 2010). "The attachment strategy of English Ivy: a complex mechanism acting on several hierarchical levels". The Journal of The Royal Society.
  4. ^ a b c Huang, Yujian (April 2016). "Nanospherical arabinogalactan proteins are a key component of the high-strength adhesive secreted by English ivy". Proceedings of the National Academy of Sciences of the United States of America.
  5. ^ a b Lenaghan, Scott (October 2013). "Isolation and chemical analysis of nanoparticles from English ivy". The Journal of the Royal Society.
  6. ^ Xia, Lijin; Lenaghan, Scott C.; Zhang, Mingjun; Wu, Yu; Zhao, Xiaopeng; Burris, Jason N.; Stewart, C. Neal (2011-03-01). "Characterization of English ivy (Hedera helix) adhesion force and imaging using atomic force microscopy". Journal of Nanoparticle Research. 13 (3): 1029–1037. doi:10.1007/s11051-010-0091-3. ISSN 1388-0764.