Talk:2009 Group Project 4

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Revision as of 08:53, 1 October 2009 by Z3223194 (talk | contribs)

peer reviewing

--Bronwyn Lewis-Jones 08:53, 1 October 2009 (EST) Congratulations on a great assignment. There are so many good things about this page. I think the biggest (and easiest) improvement to be made is to cut down on the amount of headings for the History and Current Research. The headings used such as "What did they do?" etc are helpful in showing the reader what exactly they are to understand from what is written, however they interrupt the flow and spread out the information so that it seems rather daunting. If you can summarise each section into a few sentences then I think that will not only reduce your contents section to a more useful size but also make the page more reader friendly. If you don't like that idea you could strike a happy medium by either having you "What did they do..." to bold instead of a heading or have (in bold or italics) a very short summary sentence under the name followed by a short few sentences. This would still give the reader an impression of what do get out of each section but would increase the flow inside and between notable researchers etc. Hope you find this helpful. :)

--Julianna Lam 01:31, 1 October 2009 (EST) - the history section is TOO long ! the structure of the history section is good, i liked the whole idea of the sub headings ie ' what did he do?' but i think you guys included way too many people in there. the layout of the history section is not very neat and very inconsistent. you provided pictures of some people but didnt provide pictures of others. there are gaps everywhere and it just looks really messy.

- the stages and timeline parts are really good. the table looks really nice. and i especially like the pictures, very well labelled.

--Jenny Guy 18:46, 30 September 2009 (EST)


  • The history is wayyyy too long. Seriously, there are too many sub sub sub headings. Cut it down and for each scientist make it a paragraph instead of so many dot points. I almost couldnt be bothered reading them all. Definitely not a good way to represent information. Looks as though you gave up on looking for pictures of the scientists. I would too if i had that many of them. Pick the main scientists that caused a breakthrough instead of listing all 1000 of them. Also, it is inconsistent if you did decide to keep the subsubsubsub headings as 'what he did', "what he found" and "what the importance" are generally all targeting the same question.
  • I think you guys are confused as your information is conflicting. Humans have 23 pairs of chromosomes. In your introduction you state they humans and mice have the same number. However in the genetics it states that mice have 20pairs. What is true?
  • There are a few gaps (large random spaces) in the genetics sections. Might want to format this a little.
  • For the current research see the same massive point i mentioned first....
  • Your referencing in the bibliography is inconsistent. Stick with one type of system, e.g. apa OR harvard. Some of the references aren't even referenced properly. You must reference websites.
  • You haven't referenced ANY of you text. How do we know you havent just cut and paste? You need to either reference within the text (e.g. Andrews, E.A. (1895) states .....) or at the end of sentences/paragraphs with (Andrews 1895) or the number used in the bibliography.

--Sadaf Masood 15:43, 30 September 2009 (EST)Hey Group 4! Congrats on your great project guys! I have listed few points that might help:

1. Very well researched History section, lots of people doin lots of work..maybe you can make it a little short as its just a little too much info on them.

2. A bit more proper formatting, lots of gaps after every picture and table, maybe you can get rid of them

3. Timeline is great, just enough info to make sense and needed.

4. 'Why use of mouse is important?' this issue is well discussed. Great work!

5. Impressive hand drawn diagrams, any chances of making them a little larger on the main page? it would look really good!

6. Glossary is also needed...will make our life easier is understanding few words.

Rest is all well guys. The current research Section is awesome, very informative and lots of details. Its a great project guys...Best of Luck!!

--Gabriela Pinget 12:59, 30 September 2009 (EST) Hello! constructive criticism as follows:

- intro is a nice ease in but needs to be edited for grammar

- wow the history section is very well researched. I like that you've included so many contributors but are you sure you need to go into so much detail? It looks a little cluttered and detracts from the overall purpose of the assignment. Think about cutting down on it a little

- I really like the staging of embryonic development section! very engaging and well formatted! well done

-I also liked the timeline of development. I like that there was not too much information at each stage, but just enough to give a clear outline. Maybe a link to find out more would be useful

- genetics section is perfect

- again, the current research section is a little too spread out. The continuous "what did they do..." works well to begin with but after a while gets to be too much

Overall, a really nice looking page

--Joe Nassif 17:59, 29 September 2009 (EST)

Awesome looking wiki page, mouse group 4 an excellent assignment.

It is a really interesting reading and viewing your wiki page the content flow really well when reviewed.

1. The assignment is impressive it outlines the point with the use of sub headings which is always useful in the project as a referencing point.

2. (What did he do?) and (What did they find?) is a great way to state the history as it allows the reader to quickly get the brief information and understand it , also the illustrations throughout the assessment was great it referred to the text really well, which supported the info impressively. The hand drawn images in the (staging) and (timeline) sections were extremely great the detail was impressive.

3. Some ways to improve the assignment: A) There are some unnecessary data throughout the project which are not relevant for example the ‘length of mouse embryo’ , removing this sections can truncate the assignment which would enhance the structure.

B) Current research information on the background of the research finders reveal great info on the development of the model usage, the findings and the relevance to human embryology have been summarized greatly.

C) The referencing need to be fixed in proper format. Visit : for help with APA referencing

D) a glossary is needed to help the reader understand terms.

Overall a great project. The criteria was covered really well it, stated specfic topic in regards to the mouse and it embryonic developent which group 4 has summarised really well.

--Joe Nassif 17:59, 29 September 2009 (EST)

--Mitchell Mathieson 09:39, 25 September 2009 (EST)Page looks good. I liked how there was heaps of information on the genetics and the current research (however, this was a bit too spread out maybe). There seems to be a lot of gaps in the text, so the formatting could be maybe tightened up. The references maybe should be formatted better, and there is repeated information (tables and text for stages), but I really like how clicking the image goes to another page with more information...that is cool. The drawings are cute as well. Overall very good, I think formatting was the downfall from that, but the information is top notch.

--Jin Lee 16:42, 26 September 2009 (EST) hellow group4~ very impressive assignment guys!well done! I really enjoyed reading your assignment. it was easy to read and the information was relevant. However, I found the formatting of the images and texts were too sqeezy. may be resize the images and line up with the relevant information. Also, I think the reference needs to be looked after as well. Overall, the contents of the assignment is very useful and interesting.

--Vishnnu Shanmugam 20:02, 26 September 2009 (EST)Congratulations mouse group on an excellent assignment. It is a real joy to read. One of the best features of the assignment is how it gets straight to the point with the use of sub headings “What did he do?” & “What did they find?”. Even the images used throughout the text are interesting, especially the fully labeled hand drawn images in the “staging” and “timeline” sections. Some ways to improve the assignment:

-There are some unnecessary graphs in the assignment such as “the average length of mouse embryo”, “number of cells” and “number of somites”. These could perhaps be combined into a single graph. It will also reduce the congested appearance of the assignment as it seems too densely packed with no particular focus.

- In current research section, it is advisable to reduce the number of research and focus on just a few but provide more comprehensive information on the background of the research, the findings and the relevance to human embryology. It currently contains too many different types of research that have described very briefly.

- Edit the "content" section at the top of the page as it's length seems to be getting out of control. It is perhaps better to exclude the sub headings “What did he do?” & “What did they find?” in the contents.

- The referencing in the text need to be completed as there are some sections well referenced and others with no referencing. see for help with APA referencing

- A Glossary would also complement the text.

Overall a classy project, only some changes necessary

--Gang Liu 16:49, 27 September 2009 (EST)This is one of the better wikipage i have seen so far. It demonstrates not only extended literature research skill, but also an in-depth understanding of the topic. The content of this page has been consistent throughout. In addition, paragraphs are straigtforward and concise, and make the point. Detailed texts with accessory graphics are appropriate in here. In paticular, history section. It describes the model use in terms of details of experiment, and results of experiment. Stages and timeline are very self-explanatory and visually enhanced.

This project can be improved by considering the following points.

  • Lack of glossary list. Need to provide meaning of words such as "polyestrous", "oocyte", "Ectoderm", "endoderm", etc;
  • Reformat stages section. I found this section a bit "busy". Might considering resize the pictures.

Last few words. I have learnt from this page that mouse has the same size genome as the human genome; Mouse genes can be easily manipulated and studied; Mouse a high degree of homogeny with humans. Well done!

--Thomas Dangerfield 14:12, 28 September 2009 (EST)Hey guys! Wow so much info first off! Not entirely sure we need to know about everyone involved in the history, maybe could have collaborated and joined people together or possibly even left certain people out. To me, the whole page is like how mark described, with everything all one great smudge of info with no real formatting or sequence or continuation. It was just kind of like an overload and reading it was a little difficult at some stages. Also corresponding the images in the timeline could have been included in the text.

Also I think your numbering of figures is a little off in the timeline section, with figures 1-4 on the right and then you have figures 4-7 describing stages 12-14. Just seems that there is two figure 4's for two different images.

Love the large amount of research and information, but could just work on your presentation and you'll do fine! Great work guys!

--Sumaiya Rahman 16:56, 28 September 2009 (EST) Hey guys! Overall a very nice assignment with a great deal of information! You can tell you guys did a lot of research. The contents are massive! Maybe you could cut this down and not use so many subheadings such as “what did they do?”, “what did they find?” and only have a subheading for each researcher. The introduction is well written. The history of model use has some really good information. My only criticism in this section is that there are a lot of gaps and blank spaces. You just need to delete all the spaces. The staging section showed a lot of research and effort. Well done!! The only thing is, is it a bit too much? There are a lot of tables and images that it was hard to keep track. Maybe this could be set out differently and made to look less busy. The timeline of development is fantastic and set out really well. It is very easy to understand and the drawings are great! Once again the current research is very spread out with lots of spaces. Also adding a glossary may help the readers in understanding the text. GREAT JOB!

--Carly Mooney 11:49, 29 September 2009 (EST) I think all your material is there but the page layout needs work. Especially the history of the models use.

  • The spacing and images are inconsistent. I liked the history of timeline section information and how it was presented, just the spacing of it all needs to be even.
  • The stages of embryonic development was a little all over the place, and very daunting to look at.
  • A glossary would help.

I think you guys did a really good job and just have to work on presentation.

--Joanne Raffel 16:14, 29 September 2009 (EST) Very impressive page, however it was very long!!! The introduction was very clear and concise. The history section was extremely long and poorly formatted, there were too many pictures with too little information, I would recommend cutting some of the images and just keeping the pictures of those who made a significant impact upon the mouse embryo, I also thought it was unneccessary to write after each subheading, what did he do and their result, I would prefer if it was just one paragraph. Your main heading were overshadowed by the subheadings and the rest of the text. There is a lot of information for the staging section, which is good however it can made it difficult to read, I would recommend having some of the information linked onto a separate page. The picture and format for the timeline section was exceptional however it lacked information, I also thought that it was irrelevent rewriting the timeline after the pictures, I would recommend including it with the picture rather than after it and the graph size made it seem insignificant. The genetics section was very extensive and I thought some of the information was better included with the current research. Similar to the history section, I thought the formatting of the current research section was very unorganised and too spaced out. Overall a very nice page.

--Mark Hill 01:46, 8 September 2009 (EST) Well the content is there now, but what a mess, and I am not just talking about the formatting problem which can be easily fixed, you have no structure to your project, its not a matter of throwing everything at a wall and seeing what sticks. Work together for an integrated coverage. Timeline of development, is not the way to start your page with a huge table of data.

--Mark Hill 08:43, 21 August 2009 (EST) OK guys, time to see some actual content uploaded on both your discussion and project pages.

   * Timeline of Development - how long (Emily)
   * Staging - are there species specific staging, what occurs when (Elide)
   * History of Model Use - when was it first used, what embryology research (Begum)
   * Genetics - chromosome number, sequencing (Angama)
   * Current Embryology Research - research papers and findings (All)

Here is a link for timeline [ ]

link for the mouse brain development timeline

hey guys there is another interesting link about mouse development

Hey Emily. The link below has a timeline that you can check out in your spare time. Begum. [1]

Hi girls, here is a link to a text book about mouse embryology it looks pretty good. hope it can help [2] let me know if the link doesnt work. Ive been working on the main page, so have a look and tell me what you think, Also what are we doing about references? If we have used information but put it in our own words do we need to put in text citations,or do we just reference the journal at the end? I just want to be very careful. Thanks!

Hey Elide, i think your work is looking really good. its very easy to read and understand. keep going!!!! emily

hey everyone, I have uploaded some of my timeline work. I'm not sure if I've gone into to much detail or not and also on how is best to present the timeline. It is fairly basic and definately needs some work - especially on presentation, grammar, etc. let me know what you think. Emily

 good site for stages or timeline- atlas of pictures of stages- The Edinburgh Mouse Atlas Project [3]

Hello girls, it's Begum. I put some info under the history section. Wanted to let you all know that I've got a fair bit of info, and I will do my part as best as I can. Btw Emily, I think maybe dot from would be best for you, but if you can use those lines that I was talking to you about on Wednesday, that would be great...I know it's hard.

hey everyone, i have put some info under the genetics heading and some under research. I am still struggling to find the appropriate info related to the topic of genetics because there is alot of info abt the different types of stains used in labarotories but not the genetics. I emailed Dr.Hill and have asked him what to include in my section specifically,hopefully he will help. So far i have just started it needs alot of more work to be done,girls just read thru my section n leme know wt u think of it. have a nice weekend everyone. Angama.

Hi girls! Begum, you history info is really good. If very interesting! I really like how you are doing it in order of dates of discovery and what they did, what they found etc! Cant wait to know more. Angama, your doing well! it sounds like your finding the info hard to get. I'll keep an eye out for you! If your stuck on what you sound be doing then i might have a few ideas. I remember Mark Hill saying that you should compare the genome to the humans genome. so maybe if the genome is the same size as the humans, could you descibe similarities or differences? I know that there is a link to the mouse genome on the mouse web page he gave us ( next to the discussion link). Are you just ment to list the mouse genome sequence? could you go into what genes code what, eg which one codes for the sex linked gene, is it the X and Y gene etc? hopefully Mark gives you some ideas. well as you might have noticed i've been adding to my stages. the only thing is im worried about there being too much info up there. basically ive tried to get all the info available included in my stages to make sure i cover everything, and then later i'll go over it all and edit and polish it up a bit. Ive done some drawings to the best of my ability, but i can scrap them if you all think they arnt professional enough. just thought i'd try to present the information differently. let me know if you think i'm including too much information. i think i'm having the same problem as you begum, there is lots of info! Elide

Thanks Elide. I'm trying. (Again, loved the artwork!)Btw, Emily, I had a think about your section and I think it might be too much 'clicking' back-and-forth if we link the displayed pic to the 'info' page. Don't stress, you've got the info (heaps which is excellent) but make sure you get some pictures soon so we can start drawing (I'm helping with the drawings as well ok). Mark said 'Nature' and 'Science' have useable images so lets make that our start. BTW, I will be using the question mark symbol(???) so I don't forget to reference. Begum

Hey everyone, I have found an online text book. it has a chapter on genetics and history and a lot of other stuff. [4] Emily

Hey girls. If you've seen my section, the info is not on the main page, but linked to another page. I thought that it might make everything look more neat. I thought we could all do it like that. It's just an idea. Something different. Maybe we could have something on the main page (picture of a mouse). Your thoughts everybody? Begum

hey begum, ur work looks really good. i like the idea of linking the work to another page. - we don't have to worry about to much info being on the front page and it gives people to option of viewing the work if they want to. ive been working on drawings, i'll show them to you next week but am not sure how to upload them at the moment. Emily

Thanks! That sounds great that you like the idea. About the photos that you are drawing, if there by hand, you can scan them somehow. But overall, 1. click 'Upload File' on the left hand side of this page 2. New page comes up: click 'Browse' and choose your file that you want to upload. 3. Name it (under the Browse button) NOTE: write down what you named the file as because like Elide says "'s going to be lost in space!..." 4. Write down info/comments (like who is the author (YOU), and if the drawing is based on a picture) 5. UPLOAD! 6. Go to your section and just normally type this down to the area you want the picture to be seen:


Your thoughts Angama and Elide? (about the linking of our sections to separate pages?) Begum.

Oh and another thing: What do you girls think about my page, I've got a heading for each DATE and underneath each there are further subheadings (e.g. 'What did he do?'. Should I change them to just text, I mean, does it look messy with sub-sub-headings? Begum.

wow girls! great work.. okay so i asked mark about a new page and he said to avoid it because our info is meant to be on our one page. he said if there is extra information on what we wanted to say but is too much for the main page then have a link to our discussion page. (which is what im going to do) Begum your new page is fantastic!! you have done lots of work! but why dont you just put it on our main page? also girls i think we are getting too carried away with info. just keep it simple! i'm sorry i havent been around this week to work on it but i plan to get going asap. just fixing up some things, summarising, writing introductions etc. did you all read his note about slabbing info onto our page?? how about some introductions, and sentences to ease ourselves into the content. planning on trying to work on that now anyway..

also lets get the information flowing. why dont we go intro, history of model use, stages, timeline, genetics, then current use.. what do you all think?

hey, i thing that that sounds like a good, logical way to do the page. i've finished the drawings, just need to upload them. About the timeline information, is there anything specific that i should include. the stuff that is on the page is a little vague and so i need some advice as to what are key points that i should include. i know that the drawing are very simplistic, let me know wjat you think about them. ive put one up below. i just need a way to link it to text. emily

Thanks Elide. You know, I think that's a great idea. Have it all on one page, seems less 'diverging...', seems more COMPLETE. I love the ORDER as well. I'll fix all that up!

Hey girls, please have a look at what i've done on the timeline. the images are all hand drawn based upon the text: 'the house mouse'. if anyone could give me any ideas on how best to present the pictures - which would be better - next to or below the text? keep in mind that it is incomplete and there is an illustration for each day of development (i.e. 19 in total). if you think that is too many let me know, some may be similar to Elide's ones. Also, do you think i should put some colour into the drawings? Emily

I love your work Emily. All you need to do is put the info on the growth of the mouse that is on the main page, onto the page with the graph of the growth of the mouse embryo...we talked about that before any way-AND I think your parts finished! Begum. Angama, I added something to the end of your section that I thought was interesting. Have a look. And are you mentioning manipulation and 'shut-down' of the genes in your section?? Begum. To everyone, apparently Mus Musculus is the scientific name of the common house mouse, not the mouse. I was thinking of editing that.

HEY EVERYONE! well i've added in some pictures just to make it look more visual, change them if you have better ones.. and i'm going to be working on the current research section tommorow. oh i also added some graphs like we thought of for emilys section.. so i think my section is finished finally! what do you think? can i just say, I think the whole thing looks great! you girls have been a pleasure to work with! :) Thanks so much!!

hi girls, i am sorry..i have been very busy during the mid-sem break and i know we all had our exams and assignments due. but i was having some issues in my family and also the exams and assignments so didnt really had the chance to read wat u girls have got on the main page. i just finished reading thru it and it looks amazing..WELL DONE GIRLS!! you all have done a marvellous job...Eldie and Begum thanks for suggesting some main points to add for the genetics.i am currently working on it.. hopefully tonight i will have all the information on the page..Begum i love how you have presented alot of info into a very easy and understandable makes so much sense..n it looks very nice with the pictures. Eldie and Emily great amount of work and the pictures and the graphs are superb. i just had a look to other groups pages. n i think so far our page looks very interesting with concise info n amazing pictures. n Begum yes i read what you have added thanks for tht..i will cu girls around..gudluck everyone. cheers. Angama.
Girls can you please help me out.. i am so annoyed..

like rite now i was typing some info and when i clicked to save. it says "conflict" so i think some one else is also editing the page at the same time that i am. and i lost all my work..arghh.. so which means i have to type it all again. is there any other way that it tells me that someone else

is also using it so i dont click on save or even preview 

because when i do tht i lost all the work tht i had. If anyone knows please let me know. thanks. Angama.

Current research : I have put some information in the current research part. not sure where they should be put. Begum, as discussed you can edit it or place it in its appropriate place.

Don't stress Angama at all, now you know, it will be over soon. Uploading it easy:

1. click 'Upload File' on the left hand side of this page

2. New page comes up: click 'Browse' and choose your file that you want to upload.

3. Name it (under the Browse button) NOTE: write down what you named the file as because like Elide says "'s going to be lost in space!..."

4. Write down info/comments (like who is the author (YOU), and if the drawing is based on a picture)

5. UPLOAD! 6. Go to your section and just normally type this down to the area you want the picture to be seen:

It's easier than it is typed! Of you still have problems I will be at the embryo lab, of there is exams there the ANAT LAB opposite to it, if not Level 3 library computers.

maternal diabetes alters transcriptional programs in the developing embryo, mammary gland development in MMTV-CBLC transgenic mouse, hedgehog signalling inhibits palatogenesis and arrests tooth development in a mouse model of the nevoid basal cell carcinoma syndrome., Fibroblast growth factor 18 gives growth and directional cues to airway cartilage.

Hi girls, i think i have completed my section. could you all please just read thru it and leme know wat you think of it. i did it to the best of my ability. Hopefully you will all like it if you girls think therez anything more to add or to delete leme know..thanks. gudluck girls. Angama.

Angama your work is fantastic! Thanks so much! im sorry i wasnt around to help you with the problems. hope it went okay. your info is perfect! im very happy with our page! lets hope everyone else is :)

I love it Angama, good work! And the pictures you uploaded are very interesting. Cool. Awesome. Your done!! Begum.

Thanks Begum :) Girls gudluck and cu all tomorrow. Angama.

Staging of mouse embryo development

Theiler stage 6-11

Table 2: Mouse embryonic staging from blastocyst implantation to pre-somite formation (Theiler stages 6 to 11)
Theiler Stage Embryonic age in Days Post Coitum (dpc) Stage Characteristic Cell characteristics
6 4.5 (range 4-5.5)

Human carnegie stage: 4

Attachment of blastocyst


Embryonic Endoderm present covering the blastocoelic cells of the inner cell mass.
7 5 (range 4.5-6)

Human carnegie stage: 5


-Egg cylinder formation

-Ectoplacental cone

Inner cell mass increases in size

-Epiblast formation (enlarged mass)

-Proximal cells are cuboidal in shape

-Mural trophectoderm is lined by primary endoderm

8 6 (range 5-6.5)

Human carnegie stage: 5

Differentiation of egg cylinder into embryonic and extra-embryonic regions

-Pro-amniotic cavity formation

Trophoblast giant cells invade maternal tissue

-Maternal blood invades the ectoplacental cone

-Reichert's membrane appears

-Implantation site is 2x3mm

9 a) Pre-streak Advanced Endometrial and egg cylinder stage

-First evidence of embryonic axis

Morphological difference can be seen between embryonic and extra-embryonic ectoderm

-Maternal blood further invades ectoplacental cone

-Uterine crypts lose their original lumen

9 b) Early streak Gastrulation begins (later in stage) First mesodermal cells produced
10 a) 7 (range 6.5-7.5)

Mid streak to late streak Human carnegie stage: 8

Amnion formation The amniotic fold starts to form from posterior tissue of primitive streak bulging.

-Allantoic bud evident -Gastrulation continues -Primitive node visible -Amnion begins to close

11 7.5 (range 7.25-8)

Human carnegie stage: 9

Formation of neural plate and presomites Amniotic cavity is sealed to form 3 cavities (amniotic cavity, exocoelom and ectoplacental cleft)

-Allantoic bud elongates -Notochodal plate can be seen in the midline and subjacent to neural groove -Head form from the enlargement of the rostral end of neural plate (early head fold) -Formation of foregut pocket begins

Theiler stage 12-14

Theiler stage Embryonic age in Days Post Coitum (dpc) Stage characteristic Cell characteristics Number of somite pairs
12 a) 8 (range 7.5-8.75)

Human carnegie stage: 9

unturned embryo

-1st appearance of somite pairs

allantois extends into exocoelom

-maxillary components of 1st brachial arch prominent -visible preotic sulcus in 2-3 stomite embryo -formation of cardiogenic plate begins - foregut pocket visible

12 b) 8 (range 7.5-8.75) unturned embryo

- formation of somites 5-7 -abscent 2nd branchial arch

prominent headfolds

-neural closure at site of 4th and 5th somites closing in caudal and rostral directions -optic placodes visible with indentation of optic pits -rapid development of heart rudiment -allantois comes in contact with chorion

13 8.5 (range 8-9.25)

Human carnegie stage: 10

turning of embryo at around 6-8 pairs

-3rd branchial arch absent

1st branchial arch with maxillary and mandibular components

-2nd branchial arch visible - regionalization of heart visible -neural tube closure at point opposite outflow tract to proximal part of tail -notocord and prepancreatic endoderm contact remaining

14 9 (range 8.5-9.75)

Human carnegie stage: 11

anterior neuropore formation and closure (at 15-18 somite pairs)

-forelimb bud absent

optic pit becomes more indented

-mandibular process of 1st branchial arch visible -3rd branchial arch visible -prominent ridge on lateral body wall at 8th-12th somite


Theiler stages 15-20

Table 3: Mouse embryonic stages from Theiler stage 15 to 20 ( somite stages)

Theiler Stage Embryonic Age (dpc) Stage Characteristic Cell Characteristic Somite Number(pairs
15 9.5 (range 9-10.25)

Human carnegie stage: 12

Formation of Forelimb bud

-Posterior neuropore

8-12th somite pair condensation of forelimb bud is visible

-Hind limb bud appears

-Forebrain vesicle division into telencephalic and diencephalic vesicles

-Lung development commences

-1st sign of Pancreas morphogenesis of dorsal pancreatic bud (22-25 somites).

16 10 (range 9.5-10.75)

Human carnegie stage: 13-15

Caudal neuropore closes

-Hind limb bud (23rd-28th somite) and tail bud

Concave 3rd and 4th branchial arches.

-Rathke's pouch formation

-Nasal processes formation.

-Ventral pancreatic bud appears

17 10.5 (range 10-11.25)

Human carnegie stage: 13-15

Deep Lens Indentation Lens pit is deepened and has a narrowed outer opening.

-Physiological umbilical hernia present.

-1st branchial arch divides into maxillary and mandibular components.

-Advanced development of brain tube

-Tail elongates and thins

18 11 (range 10.5-11.25)

Human carnegie stage: 13-15

Closure of Lens Vesicle Cervical somites no longer visible

-Brain rapidly grows

-Formation of nasal pit

19 11.5 (range 11-12.25)

Human carnegie stage: 16

Lens vesicle separated completely from surface

–Closed and detached from ectoderm

Well Defined eyes and their peripheral margins

-Forelimbs divided into two regions

-Proximal part of the future limb-girdle and 'arm'

-Peripheral part forming a circular or anterior footplate.

-Otic pit medial and lateral margins move together

-Auditory hillocks visible

20 12 (range 11.5-13)

Human carnegie stage: 17

First sign of fingers Anterior footplate no longer circular (develops angles)

-Posterior footplate visible

-Pigmentation of retina visible

-Tongue and brain vesicles identifiable