From Embryology

Lab Attendance

Lab 1 --Z3220343 11:49, 25 July 2012 (EST) Lab 2 --Z3220343 10:56, 1 August 2012 (EST) Lab 3 --Z3220343 10:06, 8 August 2012 (EST) Lab 4 --Z3220343 10:05, 15 August 2012 (EST) Lab 5 --Z3220343 10:02, 22 August 2012 (EST) Lab 6 --Z3220343 10:08, 29 August 2012 (EST) Lab 7 --Z3220343 10:12, 12 September 2012 (EST) Lab 8 --Z3220343 10:01, 19 September 2012 (EST) Lab 9 --Z3220343 09:58, 26 September 2012 (EST) Lab 10 --Z3220343 10:05, 3 October 2012 (EST) Lab 12 --Z3220343 10:17, 17 October 2012 (EST)

Full lab attendance logged --Mark Hill 07:20, 18 October 2012 (EST)

Lab 1 Assignment

    • The history of IVF dates back to the 1890's with Walter Heape reporting embryo transplants in rabbits. It was not until 1965 that Robert Edwards, Georgianna and Howard Jones, attempted to fertilize human oocytes In Vitro. In 1973 the first IVF pregnancy was reported by Leeton and Wood at Monash University (Melbourne, Australia) but this resulted in a miscarriage. The first IVF birth was the famous Louise Brown, born in 1978. This birth was the result of the collaborate works of Robert Edwards and Patrick Steptoe. [1]
  • In 2010 Robert Edwards won the Nobel Prize in Physiology or Medicine for his work with In Vitro Fertilization. [2]

Demián Glujovsky, Debbie Blake, Cindy Farquhar ,Ariel Bardach. Cleavage stage versus blastocyst stage embryo transfer in assisted reproductive technology 11 July 2012

The purpose of this article is to determine whether implantation of a ‘cleavage stage’(2-3 days) embryo is more likely to result in a live birth or if implantation should occur later when the embryo has reached the ‘blastocysts’ (5-6 days) stage of development. While there have been papers published on the success of ‘blastocysts’ implantation, it is noted that these trials were not randomised nor a consensus about the best practice for blastocyst culture. This paper delves into the results of a clinical randomised trial on blastocysts against cleavage stage. The merits found towards blastocysts are based on 2 arguments. 1. That most successful pregnancies in vivo, the embryo does not reach the uterus at day 3, which is the typical implantation time for cleavage transfer. 2. That blastocysts have higher implantation potential as the embryo have reach the blastocysts stage, have the most potential to survive. It is this second point, the one of self-selection which is seen a negative in the use of blastocysts implantation. This study found that although the live birth rate for the randomised controlled trail for blastocysts was a small but significant difference, the miscarriage rate between cleavage stage and blastocysts remained the same. On a whole this paper found that the benefits between cleavage stage and blastocysts are still unclear. [3]

--Mark Hill 17:46, 10 September 2012 (EST) Excellent answers to both questions 10/10.

Lab 2 Assignment

  1. Image:Fly GenomeJournal.pbio.0050131.g001.png[1]
  2. Trophinin is a protein that is expressed by trophoblast cells. In vivo pattern and activity of this protein suggests that it assists in the initial attachment of trophectoderm cells into the maternal epithelia. It is also instrumental in allowing the trophoblasts to invade through the uterine wall. [2]


  1. Gross L (2007) Novel Technique Shows When the Fertilized Egg’s Genome Comes into Its Own. PLoS Biol 5(5): e131. doi:10.1371/journal.pbio.0050131
  2. <pubmed>17487845</pubmed>

--Mark Hill 17:52, 10 September 2012 (EST) 1. Image uploaded with all required information including copyright and student image template. 2. Trophinin protein related to implantation identified, the paper though related to cancer progression and also without description of mechanism (role). See also PMID 22717627 8/10

Lab 3 Assignment

1. Gestational Age - is the period between conception and birth. It is determined as the time form last menstrual cycle to birth and can be between 38-42 weeks.[1] Post fertilization age - is determined as time from the fertilization of the egg. This time frame is 2 weeks shorter than gestational age and in most cases must be inferred. [2]

Gestational age is used in describing human development is traditionally used as most wopmen know when their last period was and not when conception occurred. There is minor error of 4-6 days. It is also conveniently broken up into weeks.[3]

2. Somites differentiate into 2 parts:

  • The ventromedial part is the sclerotome, which cells become the vertebrae and ribs (bone).
  • The dorsolateral part is the dermomyotome, which cells from the myotome regions – muscles and the dermatome regions becomes the dermis.[4]


  4. The Developing Human: clinically oriented embryology 9th ed. Keith L. Moore, T.V.N. Persaud, Mark G. Torchia. Philadelphia, PA: Saunders, 2011. Chapter 5 pg 343

--Mark Hill 17:58, 10 September 2012 (EST) 1. Answer is detailed and correct. 2. You have identified 3 somite regions and histological tissue types. I would have preferred bone, skeletal muscle and connective tissue as the full histology descriptions. 9/10

Lab 4 Assignment

  1. Amniocentesis involves taking a sample of amniotic fluid transabdominally by a syringe. This treatment is done usually at week 15 or 16 but can be done at 10 to 14 but with a greater risk of complications.
This treatment can screen for the follow abnormalities:
  • Chromosomal and Neural tube defects.
Chorionic villus sampling involves taking a biopsy of tertiary villi from the chorion frondosum either transcervically or transabdominally. Unlike other methods CVS allows for earlier testing, generally between weeks 10 and 12.[1]
This treatment is used to screen for:
  • Cystic fibrosis and Down syndrome [2]
  1. Reversal of type 1 diabetes via islet β cell regeneration following immune modulation by cord blood-derived multipotent stem cells. January 10 2012
Cord-blood stem cells are being used to re-educate the lymphocytes in a type 1 diabetic patient. This treatment may also allow for a repopulation of islet beta cells in the pancreas. This method takes blood from the patient and the lymphocytes separated out. The lymphocytes are slowly passes through discs which contain adherent CB SCs and are then collected and returned to the patient’s blood. Type 1 patients after receiving this treatment has increased metabolic function and decreased autoimmune results lasting months after a single treatment. This paper states that they have data to prove that reversal of autoimmune response leads to regeneration of islet beta cells and improvement in metabolic function for long standing Type 1 patients.[3]


  1. Robert L. Nussbaum, Roderick R. McInnes, Huntington F. Willard, Genetics in Medicine Chapter 15 prenatal diagnosis, Saunders, 2007
  3. <pubmed>22233865</pubmed>

--Mark Hill 17:59, 10 September 2012 (EST) You have answered both questions well. 10/10

Lab 7 Assignment

  1. (a) Muscle Satellite cells are mononucleated cell that are located between the sarcolemma and basement membrane of muscle fibres. [1]

(b) Satellite cells are activated during injury and adaptation[2]. They express regulatory factors (similar to those in development) and proliferate and fuse to form myotubes. The myotubes mature to form myofibers or will fuse with damaged muscle.[3] the regulatory factors are still debated with some research suggesting that HGF[4] and another that an insulin like growth factor[5] be responsible for the activation of these cells.

2. When the nerve innovation to a muscle is lost because of spinal damage there is loss of contractile activity and/or neurological function and as a result there is a rapid loss of skeletal muscle mass.[6]. The muscle sustains serve atrophy, in which the muscle fibre size is considerably smaller than a normal muscle fibre and the number of muscle satellite cells are reduced[6]. The atrophy affects both type I and type II muscle fibres, however there is a shift towards more type II fibres following spinal cord injury[6].


  1. <pubmed>12757751</pubmed>
  2. <pubmed>PMC1571137</pubmed>
  3. <pubmed>12757751</pubmed>
  4. <pubmed>7593208</pubmed>
  5. <pubmed>PMC1571137</pubmed>
  6. 6.0 6.1 6.2 <pubmed>22776875</pubmed>

You have answered all questions well. 10/10

Lab 8 Assignment

Vision The images you have for your page are great. They complement the information you have on your page however the historical images at the top of the page feel like they are added becuase they are images, they should have a small description and be numbered if you like to show the order they go in. As is stands at the moment I found them to be confusion and just a space filler. Under the current research heading, I think you guys would benefit from giving a brief overview of what the research is not just listing the articles. If possible you should add a part about the first person/s to discover the mechanisms of eye development. You should also add a small part about the genetic parts which cause these mechanisms.

Somatosensory The introduction is thorough and explains what your topic is about. The history of discoveries part if that is all the info you can find, why not put it in a table it would format the section so the reader can get an overview on how our understanding on somatosensory began. Your page could do with adding some more pictures in relation to the different sections of somatosensory. for e.g. you mention Meissner's corpuscles in the touch section, you could add a picture with labels so that people could have a visual to understand, as you state where they are located but lay people would not understand what dermal papillae are. I see you have an embryology and development part with no information, hopefully this will be added to in the near future otherwise don't forget to delete it. You should also add more to the glossary and have a part called external links and place your links there.

Taste The introduction is well written and very informative. You should add the history timeline directly below the introduction, because where it currently is feels like it is floating. With it after the introduction it will create a flow to your page and separate the two tables. In your development table I noted a column called images, the adding of images to show the development stage you are describing will give this section some more flair. If you are not adding images don’t forget to delete the column. Your section on adult taste and tongue is very interesting but maybe if there is a difference, i.e. newborns tongues are more sensitive to a taste than adults, a comparison would be interesting here. In abnormalities you mention p2x receptors, maybe you could add this to the glossary and give a brief explanation about what they are and do. This would be a good idea for any other receptor or genes/proteins mention above that you don’t want to explain in detail in the main section.

Olfaction The introduction while small gives a great overview on what olfactory is. You could add a small overview on what the page is about to make this part a little longer I like your table on development however there is some information in the table which is missing references, you should see to that soon and add a reference. Some images in this section would be nice and if there are not going in the table then you might want to delete the image column. The anatomy of the olfactory system is quite small; this part could possibly be added to your introduction. Kallmann’s syndrome is done very well and is quite thorough and as a result the choanal atresia section looks lacking. I would suggest adding this to the bottom of your abnormalities section and if no more information is going to be added to the page maybe state that other abnormalities include - choranal atresia and then maybe an external link. Current research section is quite detailed and I would not add anything else to this section. I did notice that Role of Odorant Receptors is just stated with a reference and no information. If nothing is to be added here I would just delete this heading.

Hearing Overall this is a well written page and is thoroughly researched. While your introduction is small it is to the point. It gives an overview of hearing, its importance and outlines what your page is going to discuss. The adult anatomy and histology part is confusing, I assume the adjacent image is related to the section and that development is a separate section. If that is so maybe the ear image should be thumb nailed or made smaller so that development looks like its own part. Some images for development would be a nice addition to the well-researched information. While the class understands what it means others searching this page will have no point of reference as to what pharyngeal arches are for example, this is only a minor problem though. The format of your development section is slightly confusing. Maybe by adding a line under inner and outer ear it would define it as a section on the respective area of development. I do like the summary of inner ear development at the end. Technologies to detect, could possibly be name detection technologies/techniques has in text citations, I don’t think that these are necessary for this type of assignment.

You have made some useful comments on the other group projects and fulfilled the assessment criteria. 10/10

Lab 9 Assignment

1.Gardiner JR, Jackson AL, Gordon J, Lickert H, Manley NR, Basson MA, Localised inhibition of FGF signalling in the third pharyngeal pouch is required for normal thymus and parathyroid organogenesis. Thymus and parathyroid are derived from the third pharyngeal pouch, with the mechanisms which differentiate these organs and separate them from the pharynx being poorly understood. [1] These researchers have discovered that the lack of two FGF antagonists, spry 1 and spry 2, in mouse models cause a failure of the organs to completely separate from the pharynx[1]. These antagonists also seem to cause thymus and parathyroid hypertrophy in this model, in the parathyroid this is caused by early gene expression defects and in the thymus it is due to reduced proliferation of thymic epithelial cells. [1]

2. Oral epithelium and neural crest derived mesenchyme are needed for tooth development. Cells from the epitheliums migrate into the mesenchyme and form the tooth germ, which then form into the bud and cap. The mesenchymal cells near the basement membrane become odontoblast which secrete dentin and the adjacent layer of epithelial cells differentiate into ameloblasts which secrete enamel matrix. [2]


  1. 1.0 1.1 1.2 <pubmed>22912418</pubmed>
  2. <pubmed>PMC3408794</pubmed>

Mark Hill

  • It is also interesting that the original spry 1 in drosophila has a role in tracheal system embryogenesis.
  • acts as an antagonist of fibroblast growth factor (FGF) signaling that patterns apical branching of the Drosophila airways.
  • appears to also be associated with cell motility.

Both parts of the assessment question answered well. 10/10

Lab 11 Assignment

Uosaki, H., Andersen, P., Shenje, L.T., Fernandez, L., Christiansen, S. L., and Kwon, C., Direct Contact with Endoderm-Like Cells Efficiently Induces Cardiac Progenitors from Mouse and Human Pluripotent Stem Cells [23056302]

Heart malformations are a common birth defect and heart disease is number 1 killer of adults worldwide. Heart muscle has limited regenerative properties, which lead to the high rates of morbidity and mortality.[1] These reasons are just a few that have lead to stem cell research into iPS cells differentiation. Pluripotent stem cell–derived cardiac progenitor cells are used to study cardiogenesis in vitro and as iPS cells have the potential to differentiate into all types of somatic cells they are a source of regenerative medicine.[1] End2 cells have been reported to promote cardiomyogenesis from human embryonic stem cells, this paper found that End2 cells can enhance CPC induction through cell-cell contact. This was done in vivo process by which endodermal cells have physical contract with nascent CPCs. And it was noted that while End2 cells are known to secrete factors involved in cardiac differentiation, they may not have sufficient levels to induce CPCs.[1] This paper concludes that endoderm-like End2 cells potentially induce CPCs in vivo, is a cost effective, simple and efficient way to induce CPCs from pluripotent cells.[1]


  1. 1.0 1.1 1.2 1.3 <pubmed>23056302</pubmed>

You have used PubMed tags correctly within the text, but not in the paper heading at the beginning of the answer (only a minor issue). You should have used single quotations and a space between the URL and the text link. Also I think you have misinterpreted the term iPS. Your paper refers to the induction of cardiac cells from stem cells, not the induced cells I was discussing in relation to the Nobel prize work. I will still give you marks for your review of the paper. 6/10