User talk:Zdanows1/sandbox
Hi! It looks like you put a lot of thought into the bryophyte article. I was hoping you would explore a few before settling on one topic. The bryophyte article sounds like it needs some cleaning and re-working. Make sure that you can find ten sources that are not currently cited on there. You need to have a substantial amount of information to add to meet the writing requirement for the assignment. I think you could get there, but you need to find sources. Lethornton (talk) 03:30, 2 March 2018 (UTC)
You have fleshed out some great ideas for your improvements to the embryogenesis article. You should post a summary to the talk page to see if anyone else is following. Make sure to include links, especially if you decide to do the auxin stuff. There are other articles about plant hormones. You should save the information on genetic regulation to see how the other sections shape up. If your improvements are seeming thorough without, you might not need it. However, it could be helpful to bring up research on model systems and how genetics has been helpful.Lethornton (talk) 19:48, 15 March 2018 (UTC)
Peer review
{Comments by section}:
Great lead! It really focuses the reader on the topic and you clarified which exact stage it is considered the embryo which is great. Integrate the bullet point because it offers a great contrast to animals to help a reader familiarize.
I like how you made it broad to angiosperms and gymnosperms for morphogenic events. I think you could mention somewhere here or later what is different about meristems and embryonic tissue Two cell stage and 8 cell stage could maybe use an image to direct readers to a visual to follow along but I was able to follow along well as it was well organized.
I feel like the further stages could be labeled by stage because there were several or just broken into smaller paragraphs.
Maybe title the section “plant hormones in embryogenesis” to be more focused on the topic if you decide not to expand on polarity and just do auxin or if you find more hormones in embryogenesis. I like that you included alternative forms, which is interesting to help different readers- both students and general readers alike.
{Comments on overall}:
a) organization- I thought the indented numbering to describe stages in 8 cell stage and alternative forms was helpful for me, but to be more organized for wikipedia, you could use italics for those stage names and explain in paragraph form. Definitely would include pictures in final just because most of this has been illustrated with stages and the stages are named for how they look for some.
b) spelling- overall spelling is good and I didnt spot any mistakes. I liked that you linked major topic words to direct readers. I don’t think you need to say “direct to this page for more info” because it is implied in linking.
c) grammar- overall, good grammar and structure to sentences. Simple and scientifically explained with just enough jargon for both a student and general reader.
d) tone- informative and educational. I thought each sentence explained ideas well and communicated in an unbiased way with balanced information from variety of sources.
e) content- article explains importance of topic and adds great details where needed. Easy to follow overall and good research in improving the topic
Feel free to let me know if you have any questions. Good luck! Mamilln1 (talk) 04:33, 27 March 2018 (UTC)
Thank you Niha! This peer review was very beneficial. You included a good amount of things that you enjoyed about the article as well as things I could improve upon. I will definitely make those corrections! Zdanows1 (talk) 18:15, 12 April 2018 (UTC)
Instructor comments: Great job expanding and bringing in useful information from your sources. Currently, the works cited section does not show up with full title and author information. Make sure that you figure out what is wrong with that list before putting your work onto a main page. I also cannot evaluate the citations that you are using. Your question about using the textbook is good. The textbook might be the only source you can find for some of the basics. I think it will be OK to use that for your information, but make sure that you are also bringing in as much science from primary literature to make your article well informed. Keep up the great work!Lethornton (talk) 02:05, 13 April 2018 (UTC)
Observations February 8, 2018 The Week 3 assignment, entitled "Evaluate Wikipedia", informed us that we should create an "Article Evaluation" heading in our sandbox. The sandbox is a personal space to practice editing and to help familiarize ourselves with WikiEdu. Because the sandbox feature is at our disposal, I am going to treat it as a journal. This will allow me to practice new editing techniques and dictate observations while going through this process. The "Evaluating Articles and Sources" training module was very helpful with learning how to cite, and re-use previous citations. In addition, I did not know that Wikipedia had a "History" feature. I enjoyed learning about this, because it acts like a safety net. This will allow Dr. Thornton to see all the edits I make, even if they are deleted, or changed, by another editor.
March 1, 2018 This week I am focused on selecting my article. To guide myself in the right direction, I completed the "Finding Your Article" training and reviewed page 6 of the guidebook "Editing Wikipedia". Reviewing this information is rather overwhelming. The "Finding Your Article" training was helpful. It informed me that I should avoid topics that are already strong, controversial, or include conflicts of interest. I discovered that good articles that need work can be found in "Categories" at the bottom of article pages. Wikiprojects are also a good place to find articles that need to be worked on. Page 6 in "Editing Wikipedia" showed me that there needs to be a balance between citations and representation on Wikipedia. I must find a topic that is well cited, but poorly represented on Wikipedia. I will explore Wikipedia to find topics that are poorly represented. I will be asking my self questions, similar to the ones in the article evaluation I did a few weeks ago. Once I discover how these articles need help, I will look on the TCNJ library databases to see if they are well cited topics.
Article Evaluation I am going to evaluate the Wikipedia article entitled "Bryophyte." Many editors contributed to the topic, and the talk page is relatively active. The view history portion of the page has shown steady edits being made since March of 2007. In addition, this is a level 4 vital-article. Based on this information, it is clear that this article should have relatively few errors. This article should be an exemplary Wikipedia article. Nothing while reading the article distracted me.
However, the section on sexuality went into too much detail. I think that the article should have talked about bryophytes being monoecious, and not about dioecious plants. There should not have been a discussion about these terms related to angiosperms. Angiosperms are seed plants, bryophytes are not. Bryophytes still depend on water for their sperm to swim. The phylogeny section well written. From what the editors wrote, it was clear that there had been controversy about bryophytes being paraphyletic or monophyletic. The writing did not indicate any personal beliefs. It stated the two points of view and concluded the article section. Overall the article was neutral, and there was no outstanding bias.
Information that was discussed in the article that was not presented in class was the section about environmental and commercial uses of bryophytes. I though this section was interesting. There were a total of 29 references in the reference section. The very first link does not work. It directs you to nature.com, but then states that the page has either been removed or is not working anymore. The link I was interested in the most, was reference 16. I wanted to know if the phylogenic information was correct and sited properly. It was correct and was used properly in the article.
Finding Your Article Germination Germination
I thought this could be a possible article I could contribute to, because it is something that interests me. I found it through the WikiProject Plants page. It is a B class article of top importance. B class means that this article has a good amount of information contributing to the topic. However, B class also means that the article is not pristine and polished, as it should be. Top importance means that the entire project believes it should become a featured article, and could really contribute to the overall goal of the project. As soon as I took a look at the talk page, I realized why it was a B class article. Many comments left on the talk page regarded immaturity and inappropriate behavior. It seems that there has been a lot of debate between individuals on this topic. There was also inappropriate content written in the actual article. Scrolling through the article, I can see that each section does not go very in depth. Most wikipedia articles are very long and cover their topics in depth. However this one seems like it could go a few steps further, to really become a cohesive article.
When I went on the TCNJ library database, there was good amount of information covering the topic. It is rather broad; which is something to consider. In the "Finding Your Article" training, it said that broad is not always better. I might want to focus on something narrow and more selective.
Pollen Tube Pollen tube
Discussing the pollen tube in lecture was so interesting to me. I thought it was incredible how you could track the difference between sperm motility from ferns to angiosperms. As sperm lost their motility, the plant itself had to compensate. "Finding Your Article" discussed looking for a topic that you are interested in. This is something that peaks my interest. In the talk page there was a strong discussion about editing. It seems that the page is constantly under attack and controversy. I think it would be interesting to try and settle this debate with information I could add to the page. However, I will not be selecting this topic, because another student has already chosen it for their topic.
Plant Embryogenesis Plant embryogenesis
Another topic I found interesting in lecture was the process of embryogenesis. I was really impressed when researchers deleted genes before the embryo started developing, to how it affected the embryo growth. I would like to highlight something like that when adding to this article. When I thought of using this as a topic, I was worried that it would already be heavily featured on Wikipedia. However, the existing article is pretty barren. There are only about four headings with no sub-sections. From what I can see, the article is not very well organized. When I viewed the talk page I discovered that it is part of the WikiProject Plants. On the page there is barely anything written, except for a comment from an editor saying that it is a big mess and it must be cleaned up. For this project it is ranked with high importance, but a start class quality. It is clear that this article definitely needs some work. However, I am glad that I will not be starting from scratch. I am ready to accept this challenge. I believe this will be the article that I choose for my WikiEdu project.
Finding Your Sources
Liu, C; Xu, Z; Chua, N. "Auxin Polar Transport Is Essential for the Establishment of Bilateral Symmetry during Early Plant Embryogenesis". The Plant Cell. 5: 621–630 – via Google Scholar. Radoeva, Tatyana; Weijers, Dolf (November 2014). "A roadmap to embryo identity in plants". Trends in Plant Science. 19: 709–716 – via Google Scholar. Goldberg, Robert; Paiva, Genaro; Yadegari, Ramin (October 28, 1994). "Plant Embryogenesis: Zygote to Seed". Science. 266: 605–614 – via Google Scholar. Thomas, T (October 1993). "Gene Expression During Plant Embryogenesis and Germination: an Overview". The Plant Cell. 5: 1401–1410 – via Google Scholar. de Jong, Anke J.; Schmidt, Ed D. L.; de Vries, Sacco C. (May 1993). "Early events in higher-plant embryogenesis". Plant Molecular Biology. 22: 367–377 – via Google Scholar. Bozhkov, P. V.; Filonova, L. H.; Suarez, M. F. (January 2005). "Programmed cell death in plant embryogenesis". Current Topics in Developmental Biology. 67: 135–179 – via Google Scholar. Maraschin, S. F.; de Priester, W.; Spaink, H. P.; Wang, M. (July 2005). "Androgenic switch: an example of plant embryogenesis from the male gametophyte perspective". Journal of Experimental Botany. 56: 1711–1726 – via Google Scholar. Cooke, T. J.; Racusen, R. H.; Cohen, J. D. (November 1993). "The role of auxin in plant embryogenesis". Plant Cell. 11: 1494–1495 – via Google Scholar. Jurgens, Gerd (May 19, 1995). "Axis formation in plant embryogenesis: cues and clues". Cell. 81: 467–470 – via Google Scholar. Souter, Martin; Lindsey, Keith (June 2000). "Polarity and signaling in plant embryogenesis". Journal of Experimental Botany. 51: 971–983 – via Google Scholar. West, Marilyn A. L.; Harada, John J. (October 1993). "Embryogenesis in Higher Plants: An Overview". The Plant Cell. 5: 1361–1369 – via Google Scholar. Laux, T.; Wurschum, T.; Breuninger, Holger. "Genetic Regulation of Embryonic Pattern Formation". The Plant Cell. 6: 190–202 – via Google Scholar. Drafting Your Article - Plant Embryogenesis After reviewing the Ada Lovelace Wikipedie article and looking over the Editing Wikipedia guidebook, I realized that the first edit I should make to the Plant Embryogenesis article is flesh out the lead section. A lead section should not contain great detail. It should be concise and allow the the rest of the article page to go in further detail. However, I think the lead page for this article is a little ambiguous and could use more information.
Lead Section Plant embryogenesis is the process that produces a plant embryo from a fertilized ovule by asymmetric cell division and the differentiation of undifferentiated cells into tissues and organs. It occurs during seed development, when the single-celled zygote undergoes a programmed pattern of DNA replication then mitosis cell division resulting in a mature embryo. A similar process continues during the plant's life within the meristems of the stems and roots.
This is the information I would like to add in order to improve this section:
begins the sporophyte generation the result of fertilization single (gymnosperms) double (angiospermes) pertinent stage in plant life cycle before dormancy and germination zygote goes through various changes and divisions in order to become a mature embryo which includes shoot apical meristem hypocotyl root meristem root cap cotyledons (nutrients) unlike animal embryogenesis, plant embryogenesis results in an immature form of the plant, lacking most structures like leaves, stems, and reproductive structures Body Aside from the lead section of the article, the rest of the page is rather unorganized. The first heading on the page is titled "Seeds", which does not make much sense. It is clear that embryogenesis takes place in the protection of the seed. However, a seed is not mature until it has a complete embryo inside of it. I want to leave some of the information in this section, because it is pertinent and useful. However, I would change the heading "Seeds" into "Three Phases" and then have these sub-headings:
Morphogenic Events
early research conducted on plant embryogenesis was focused on nutrient storage, researchers are transitioning from this stage to learn more about the morphological aspects of this topic there is no determined or universal pattern of cell cleavage in this morphology - plants are very diverse and it changes for most plant species the outline for leaves, stems, roots and reproductive structures is present in plant embryos, but they are not present in the embryo - these structures develop post-embryonically the primary tissues and organ systems are outlined during this phase there is a defined polarity in plant embryos after the first asymmetric transverse division of the zygote there is - apical cell above the basal cell smaller contains more cytoplasm after divisions this cell gives rise to the embryo proper basal cell below the apical cell much larger mostly consists of a large vacuole after various divisions this gives rise to the suspensor complex suspensor complex: includes the uppermost region of the hypophyis - gives rise to the root meristem projects the embryo in the endosperm - to absorb nutrients provides a source of hormones and nutrients for the plant embryo this complex is terminated at the torpedo stage of development - due to programmed cell death later on in the process there are three domains apical domain cotyledons shoot apex upper hypocotyl central domain hypocotyl basal domain roots In this section should I include information about genetic regulation? I have information about the gurke, fackel, monopteros, and gnom genes in Arabidopsis, which provide proof for the definition of three separate domains. Would this information be too much detail? Or no? Embryo Maturation
Arrested Development
proper timing and surroundings are required for a an embryo to transition to a seedling I am also questioning the presence of the "Somatic embryogenesis" heading on the page. It is useful information. Before reading that section I did not know one could create somatic embryos from normal plant tissue. However, because it already has its own main article, I do not think much information should be included on this page. I believe it should be mentioned partially in the lead section. I would like to add an additional heading to the page:
The Role of Auxin
auxin is a hormone related to elongation and plant regulation hypocotyl from both gymnosperms and angiosperms show auxin transport to root end of the embryo researchers hypothesize that the embryonic patter is regulated by auxin transport mechanism consequence of the polar positioning of the egg when carrot embryos were subjected to auxin transport inhibitors they are unable to progress to later stages of embryogenesis globular embryos continued spherical expansion oblong embryos continued axial growth, without the introduction of cotyledons heart embryos developed additional growth axes on hypocotyls when Brassica juncea embryos were subjected to auxin transport inhibitors, the cotyledons were fused and not two separate structures Expand Your Article Lead Section Plant embryogenesis is the process that occurs after the fertilization of an ovule to produce a fully developed plant embryo. This is a pertinent stage in the plant life cycle that is followed by dormancy and germination. The zygote produced after fertilization, must undergo various cellular divisions and differentiations to become a mature embryo. An end stage embryo has five major components including the shoot apical meristem, hypocotyl, root meristem, root cap, and cotyledons.
unlike animal embryogenesis, plant embryogenesis results in an immature form of the plant, lacking most structures like leaves, stems, and reproductive structures Morphogenic Events Embryogenesis occurs naturally as a result of single, or double fertilzation, of the ovule, giving rise to two distinct structures: the plant embryo and the endosperm which together go on to develop into a seed. The zygote goes through various cellular differentiations and divisions in order to produce a mature embryo. These morphogenic events form the basic cellular pattern for the development of the shoot-root body and the primary tissue layers; it also programs the regions of meristematic tissue formation.
Two Cell Stage Following fertilization, the zygote undergoes an asymmetric transverse cell division that gives rise to two cells - an apical cell and a basal cell. The apical cells lies above the basal cell and is much smaller. The most important aspect of the original apical cell, is that it contains most of the cytoplasm from the original zygote. Cytoplasm is the substance that contains most of the organelles; which indicates that the apical region will gives rise to the majority of the organs, like the hypocotyl, shoot apical meristem, and cotyledons. The basal cell resides underneath the apical cell and is much larger. While the apical contains more cytoplasm, the basal cell consists of a large vacuole. This region will give rise to the hypophysis the suspensor complex.
Eight Cell Stage After two rounds of longitudinal division, and one round of transverse division, an eight-celled embryo (octant stage) is the result. At this point in development there is are four definite domains:
Apical Embryo Domain - gives rise to the embryo proper (the shoot apical meristem and cotyledons). Central Embryo Domain - gives rise to another portion of the embryo proper the hypocotyl, root apical meristem, and some contributions to the cotyledons. Basal Embryo Domain - contains the hypophysis, which will later give rise to the radicle and the root cap. Suspensor - this is the region at the very bottom which connects the embryo to the endosperm, for nutritional purposes. Further Stages and Maturation From the eight cell stage (octant stage) onwards, the zygotic embryo shows clear embryo patterning, which forms the main axis of polarity, and the linear formation of future structures. After the eight cell stage, there is a sixteen cell stage and a globular stage. In the globular stage, the embryo develops radial patterning through a series of cell divisions, with the outer layer of cells differentiating into the 'protoderm.' The globular embryo can be thought of as two layers of inner cells with distinct developmental fates; the apical layer will go on to produce cotyledons and shoot meristem, while the lower layer produces the hypocotyl and root meristem.
After the early and late globular stages there is a transition phase and a heart stage. Bilateral symmetry is apparent from the heart stage; pro vascular cells will also differentiate at this stage. The heart stage is followed by the torpedo stage. During embryogenesis thus far, there has been cell growth and division, cell differentiation. However, there has not been a mention of programmed cell death yet in the discussion of embryogenesis. Programmed cell death occurs regularly throughout the growth process, like any other development. However, in the torpedo stage of development parts of the suspensor complex must be terminated. The suspensor complex is shortened because at this point in development most of the nutrition from the endosperm has been utilized, and there must be space for the mature embryo. After the suspensor complex is gone, the embryo is fully developed..
The second phase, or postembryonic development, involves the maturation of cells, which involves cell growth and the storage of macromolecules (such as oils, starches and proteins) required as a 'food and energy supply' during germination and seedling growth.
I realized when I was flushing out this portion of my article, that I only focused on the formation of organs. This part of my article does not contain enough information about the formation of dermal, ground, and vascular tissue. Would it be okay if I use the textbook to support this information? I have had some trouble finding scientific article that go in depth on this process, but I will keep searching!
Dormancy I will be adding a short amount of information here, and provide a link to the Wikipedia article "Seed Dormancy".
The Role of Auxin Auxin is a hormone related to the elongation and regulation of plants. It also plays an important role in the establishment polarity with the plant embryo. Research has shown that the hypocotyl from both gymnosperms and angiosperms show auxin transport to root end of the embryo Is has been hypothesized that the embryonic pattern is regulated by the auxin transport mechanism, and the polar positioning of cells within the ovule. The importance of auxin was proved when carrot embryos, at different stages, were subjected to auxin transport inhibitors. The inhibitors that these carrots were subjected to made them unable to progress to later stages of embryogenesis During the globular stage of embryogenesis, the embryos continued spherical expansion. In addition, oblong embryos continued axial growth, without the introduction of cotyledons During the heart embryo stage of development there were additional growth axes on hypocotyls. Further auxin transport inhibition research, conducted on Brassica juncea, show that after germination, the cotyledons were fused and not two separate structures This shows the importance of auxin the embryonic life cycle. More information can be located on the auxin Wikipedia article.
I am contemplating making an entire section dedicated to the establishment of polarity in the plant embryos and why it is important. If I go forward with that choic, I will have auxin be a subsection of that.
Alternative Forms of Embryogenesis Somatic Embryogenesis Somatic embryos are formed from plant cells that are not normally involved in the development of embryos, i.e. ordinary plant tissue. No endosperm or seed coat is formed around a somatic embryo. Further information can be found at the Somatic embryogenesis Wikipedia article.
Androgenesis In certain cases, under high levels of stress, plants can form a mature embryo from a reduced, or immature, pollen grain. This process is known as androgenesis. Embryos that result from this mechanism can germinate into fully functional plants. As mentioned, the embryo results from a single pollen grain. Pollen grains consists of three cells - one vegetative cell containg two generative cells. Androgenesis must be triggered during the asymmetric division of microspores. However, once the vegetative cell starts to make starch and proteins, androgenesis can no longer occur. This mode of embryogenesis consists of three phases:
Acquisition of Embryonic Potential - this is the repression of gametophyte formation, so that the differentiation of cells can occur. Initiation of Cell Divisions - multicellular structures begin to form, which are contained by the exine wall. Pattern Formation - embryo-like structures are released out of the exile wall, in order for pattern formation to continue. After these three phases occur, the rest of the process falls in line with the standard embryogenesis events.
Respond to Peer Review/Expand Your Article Post to plant embryogenesis talk page Hello! I am a college student currently enrolled in a seed plants course. Our assignment, focused over the course of the semester, is to edit a Wikipedia article. I have chosen this one as part of my assignment. I feel there is a lot more information on this topic that can be added to this article. I plan to flesh out the lead section and give it more substance. Then I plan to create a new heading called "Morphogenic events." Here I would include subheadings on each of the individual embryogenic stages including the two cell stage, eight cell stage, sixteen cell stage, globular stage, heart stage, and torpedo stage. I have a great deal of information on the two cell and eight cell stage. I am lacking on information from the other stages, but I plan to change that! I believe the plant growth and bud section talks about embryonic tissue than actual embryogenesis, but I think it is okay as is. Next, I plant to add a heading entitled "The role of auxin." After reading two articles on the topic, I could tell this hormone is crucial to plant embryogenesis. However, there is already a Wikipedia page dedicated to it, so I will not go into too much detail. Another heading I would add is "Dormancy." There is already a Wikipedia page dedicated to dormancy. However, it does not focus solely on plants. It covers both animals and plants, discussing why it is beneficial for survival. Dormancy would be beneficial to this article because there are two main stages to plant embryogenesis - morphogenesis/maturation and arrested development. In the literature I have gone through so far, it states that the arrested development stage and the dormancy aspect of plant embryogenesis are almost one in the same. Therefore, I would give information about dormancy and show it is beneficial in embryogenesis. Lastly, I plan to make a heading entitled "Alternative forms of embryogenesis" including information on somatic embryogenesis and androgenesis. The portion on somatic embryogenesis I plan to shorten, because there is already a Wikipedia article dedicated to it. I plan to include a short paragraph about androgenesis, and how a fully fledged embryo can form from just one pollen grain. I thought that was very interesting. The beginning stages are different, but near the end the process is the same as regular plant embryogenesis. I would put more information about this topic, or maybe even start a new page on it, but there is not enough research done yet. Here are the sources that I have found beneficial to my research so far:
Liu, C; Xu, Z; Chua, N. "Auxin Polar Transport Is Essential for the Establishment of Bilateral Symmetry during Early Plant Embryogenesis". The Plant Cell. 5: 621–630 – via Google Scholar.
Radoeva, Tatyana; Weijers, Dolf (November 2014). "A roadmap to embryo identity in plants". Trends in Plant Science. 19: 709–716 – via Google Scholar.
Thomas, T (October 1993). "Gene Expression During Plant Embryogenesis and Germination: an Overview". The Plant Cell. 5: 1401–1410 – via Google Scholar.
de Jong, Anke J.; Schmidt, Ed D. L.; de Vries, Sacco C. (May 1993). "Early events in higher-plant embryogenesis". Plant Molecular Biology. 22: 367–377 – via Google Scholar.
Bozhkov, P. V.; Filonova, L. H.; Suarez, M. F. (January 2005). "Programmed cell death in plant embryogenesis". Current Topics in Developmental Biology. 67: 135–179 – via Google Scholar.
Maraschin, S. F.; de Priester, W.; Spaink, H. P.; Wang, M. (July 2005). "Androgenic switch: an example of plant embryogenesis from the male gametophyte perspective". Journal of Experimental Botany. 56: 1711–1726 – via Google Scholar.
Cooke, T. J.; Racusen, R. H.; Cohen, J. D. (November 1993). "The role of auxin in plant embryogenesis". Plant Cell. 11: 1494–1495 – via Google Scholar.
Jurgens, Gerd (May 19, 1995). "Axis formation in plant embryogenesis: cues and clues". Cell. 81: 467–470 – via Google Scholar.
Souter, Martin; Lindsey, Keith (June 2000). "Polarity and signaling in plant embryogenesis". Journal of Experimental Botany. 51: 971–983 – via Google Scholar.
West, Marilyn A. L.; Harada, John J. (October 1993). "Embryogenesis in Higher Plants: An Overview". The Plant Cell. 5: 1361–1369 – via Google Scholar.
Laux, T.; Wurschum, T.; Breuninger, Holger. "Genetic Regulation of Embryonic Pattern Formation". The Plant Cell. 6: 190–202 – via Google Scholar. I plan to start moving my edits to Wikipedia within the next week. I would be grateful to have feedback on what I have presented here. Questions I have: Are there any errors I am making? Were there things I did not mention that this article is in need of? Please feel free to reach out to me! Zdanows1 (talk) 18:59, 12 April 2018 (UTC)
Summary of Niha's peer review Here I have included the key points from Niha's peer review that I need to improve upon:
I think you could mention somewhere here or later what is different about meristems and embryonic tissue Two cell stage and 8 cell stage could maybe use an image to I feel like the further stages could be labeled by stage because there were several or just broken into smaller paragraphs. Title the section “plant hormones in embryogenesis” to be more focused on the topic if you decide not to expand on polarity and just do auxin or if you find more hormones in embryogenesis I thought the indented numbering to describe stages in 8 cell stage and alternative forms was helpful for me, but to be more organized for wikipedia, you could use italics for those stage names and explain in paragraph form. I completely agree with what Niha mentioned here. I did reading in the Editing Wikipedia guidebook. In the section "Spruce Up Your Work", on page 12, it mentioned that headings should be use to break up the article not singular paragraphs and that numbers should not be used to section things off. Definitely would include pictures in final just because most of this has been illustrated with stages and the stages are named for how they look for some. I don’t think you need to say “direct to this page for more info” because it is implied in linking. In addition, I also responded to Niha's peer review that she posted on my talk page.
As part of the assignment it said we had to review the Editing Wikipedia guidebook. I focused on pages 12-14. In this reading it stated that as we expand our article, we should link words and topics to other Wikipedia articles in order to help the readers.
Lead Section Plant embryogenesis is the process that occurs after the fertilization of an ovule to produce a fully developed plant embryo. This is a pertinent stage in the plant life cycle that is followed by dormancy and germination. The zygote produced after fertilization, must undergo various cellular divisions and differentiations to become a mature embryo. An end stage embryo has five major components including the shoot apical meristem, hypocotyl, root meristem, root cap, and cotyledons. Unlike animal embryogenesis, plant embryogenesis results in an immature form of the plant, lacking most structures like leaves, stems, and reproductive structures
Morphogenic events Embryogenesis occurs naturally as a result of single, or double fertilzation, of the ovule, giving rise to two distinct structures: the plant embryo and the endosperm which together go on to develop into a seed. The zygote goes through various cellular differentiations and divisions in order to produce a mature embryo. These morphogenic events form the basic cellular pattern for the development of the shoot-root body and the primary tissue layers; it also programs the regions of meristematic tissue formation.
Two cell stage Following fertilization, the zygote undergoes an asymmetric transverse cell division that gives rise to two cells - an apical cell and a basal cell. The apical cells lies above the basal cell and is much smaller. The most important aspect of the original apical cell, is that it contains most of the cytoplasm from the original zygote. Cytoplasm is the substance that contains most of the organelles; which indicates that the apical region will gives rise to the majority of the organs, like the hypocotyl, shoot apical meristem, and cotyledons. The basal cell resides underneath the apical cell and is much larger. While the apical contains more cytoplasm, the basal cell consists of a large vacuole. This region will give rise to the hypophysis the suspensor complex.
Eight cell stage After two rounds of longitudinal division, and one round of transverse division, an eight-celled embryo (octant stage) is the result. At this point in development there is are four definite domains. The first domain is the apical embryo domain, this gives rise to the embryo proper (the shoot apical meristem and cotyledons). The second domain is the central embryo domain , which gives rise to another portion of the embryo proper - the hypocotyl, root apical meristem, and some contributions to the cotyledons. The third domain is the basal embryo domain, which contains the hypophysis, which will later give rise to the radicle and the root cap. The last domain is the suspensor, which is the region at the very bottom which connects the embryo to the endosperm, for nutritional purposes.
Sixteen cell stage From the eight cell stage (octant stage) onwards, the zygotic embryo shows clear embryo patterning, which forms the main axis of polarity, and the linear formation of future structures. After the eight cell stage, there is a sixteen cell stage and a globular stage.
Globular stage In the globular stage, the embryo develops radial patterning through a series of cell divisions, with the outer layer of cells differentiating into the 'protoderm.' The globular embryo can be thought of as two layers of inner cells with distinct developmental fates; the apical layer will go on to produce cotyledons and shoot meristem, while the lower layer produces the hypocotyl and root meristem.
Heart stage After the early and late globular stages there is a transition phase and a heart stage. Bilateral symmetry is apparent from the heart stage; pro vascular cells will also differentiate at this stage. The heart stage is followed by the torpedo stage. During embryogenesis thus far, there has been cell growth and division, cell differentiation. However, there has not been a mention of programmed cell death yet in the discussion of embryogenesis.
Torpedo stage Programmed cell death occurs regularly throughout the growth process, like any other development. However, in the torpedo stage of development parts of the suspensor complex must be terminated. The suspensor complex is shortened because at this point in development most of the nutrition from the endosperm has been utilized, and there must be space for the mature embryo. After the suspensor complex is gone, the embryo is fully developed..
The second phase, or postembryonic development, involves the maturation of cells, which involves cell growth and the storage of macromolecules (such as oils, starches and proteins) required as a 'food and energy supply' during germination and seedling growth.
I realized when I was flushing out this portion of my article, that I only focused on the formation of organs. This part of my article does not contain enough information about the formation of dermal, ground, and vascular tissue. Would it be okay if I use the textbook to support this information? I have had some trouble finding scientific article that go in depth on this process, but I will keep searching!
Dormancy I will be adding a short amount of information here, and provide a link to the Wikipedia article "Seed Dormancy".
The Role of Auxin Auxin is a hormone related to the elongation and regulation of plants. It also plays an important role in the establishment polarity with the plant embryo. Research has shown that the hypocotyl from both gymnosperms and angiosperms show auxin transport to root end of the embryo Is has been hypothesized that the embryonic pattern is regulated by the auxin transport mechanism, and the polar positioning of cells within the ovule. The importance of auxin was proved when carrot embryos, at different stages, were subjected to auxin transport inhibitors. The inhibitors that these carrots were subjected to made them unable to progress to later stages of embryogenesis During the globular stage of embryogenesis, the embryos continued spherical expansion. In addition, oblong embryos continued axial growth, without the introduction of cotyledons During the heart embryo stage of development there were additional growth axes on hypocotyls. Further auxin transport inhibition research, conducted on Brassica juncea, show that after germination, the cotyledons were fused and not two separate structures This shows the importance of auxin the embryonic life cycle. More information can be located on the auxin Wikipedia article.
I am contemplating making an entire section dedicated to the establishment of polarity in the plant embryos and why it is important. If I go forward with that choic, I will have auxin be a subsection of that.
Alternative Forms of Embryogenesis Somatic Embryogenesis Somatic embryos are formed from plant cells that are not normally involved in the development of embryos, i.e. ordinary plant tissue. No endosperm or seed coat is formed around a somatic embryo.
Androgenesis In certain cases, under high levels of stress, plants can form a mature embryo from a reduced, or immature, pollen grain. This process is known as androgenesis. Embryos that result from this mechanism can germinate into fully functional plants. As mentioned, the embryo results from a single pollen grain. Pollen grains consists of three cells - one vegetative cell containg two generative cells. Androgenesis must be triggered during the asymmetric division of microspores. However, once the vegetative cell starts to make starch and proteins, androgenesis can no longer occur. This mode of embryogenesis consists of three phases. The first phase is the acquisition of embryonic potential, which is the repression of gametophyte formation, so that the differentiation of cells can occur. Then during the initiation of cell divisions, multicellular structures begin to form, which are contained by the exine wall. The last step of androgenesis is pattern formation, where the embryo-like structures are released out of the exile wall, in order for pattern formation to continue.
After these three phases occur, the rest of the process falls in line with the standard embryogenesis events.
Liu, C; Xu, Z; Chua, N. "Auxin Polar Transport Is Essential for the Establishment of Bilateral Symmetry during Early Plant Embryogenesis". The Plant Cell. 5: 621–630 – via Google Scholar. Radoeva, Tatyana; Weijers, Dolf (November 2014). "A roadmap to embryo identity in plants". Trends in Plant Science. 19: 709–716 – via Google Scholar. Goldberg, Robert; Paiva, Genaro; Yadegari, Ramin (October 28, 1994). "Plant Embryogenesis: Zygote to Seed". Science. 266: 605–614 – via Google Scholar. Thomas, T (October 1993). "Gene Expression During Plant Embryogenesis and Germination: an Overview". The Plant Cell. 5: 1401–1410 – via Google Scholar. de Jong, Anke J.; Schmidt, Ed D. L.; de Vries, Sacco C. (May 1993). "Early events in higher-plant embryogenesis". Plant Molecular Biology. 22: 367–377 – via Google Scholar. Bozhkov, P. V.; Filonova, L. H.; Suarez, M. F. (January 2005). "Programmed cell death in plant embryogenesis". Current Topics in Developmental Biology. 67: 135–179 – via Google Scholar. Maraschin, S. F.; de Priester, W.; Spaink, H. P.; Wang, M. (July 2005). "Androgenic switch: an example of plant embryogenesis from the male gametophyte perspective". Journal of Experimental Botany. 56: 1711–1726 – via Google Scholar. Cooke, T. J.; Racusen, R. H.; Cohen, J. D. (November 1993). "The role of auxin in plant embryogenesis". Plant Cell. 11: 1494–1495 – via Google Scholar. Jurgens, Gerd (May 19, 1995). "Axis formation in plant embryogenesis: cues and clues". Cell. 81: 467–470 – via Google Scholar. Souter, Martin; Lindsey, Keith (June 2000). "Polarity and signaling in plant embryogenesis". Journal of Experimental Botany. 51: 971–983 – via Google Scholar. West, Marilyn A. L.; Harada, John J. (October 1993). "Embryogenesis in Higher Plants: An Overview". The Plant Cell. 5: 1361–1369 – via Google Scholar. Laux, T.; Wurschum, T.; Breuninger, Holger. "Genetic Regulation of Embryonic Pattern Formation". The Plant Cell. 6: 190–202 – via Google Scholar. — Preceding unsigned comment added by Zdanows1 (talk • contribs) 16:46, 16 April 2018 (UTC)