From Embryology
Revision as of 13:01, 21 September 2011 by Z3279511 (talk | contribs)

Lab 4 Online Assessment

  1. The allantois, identified in the placental cord, is continuous with what anatomical structure?
  2. Identify the 3 vascular shunts, and their location, in the embryonic circulation.
  3. Identify the Group project sub-section that you will be researching. (Add to project page and your individual assessment page)

--Z3279511 12:55, 28 July 2011 (EST)

Lab 1: Assessment

1. The origin of In Vitro Fertilization (IVF) lies in 1950s, where Dr. Robert G. Edwards started to work on his idea for the treatment of infertility. He was the first to show, that the human oocyte can undergo fertilization, grow into an embryo and blastocyst in vitro and then be implanted into the mothers womb to develop into a healthy infant. On the 25th of July 1987 Louise Joy Brown, the first child conceived via IVF was born. Dr. Robert G. Edwards received the 2010 Nobel Prize in Physiology or Medicine for the discovery of IVF.

2. Özer et al. showed in their study published in the Turk Arch Pediatri, that children conceived through assisted reproductive techniques (ART) have a higher risk of premature birth and multiple gestation in comparison to children conceived naturally. The study evaluated neonatal morbidity, mortality, congenital abnormalities, prematurity and multiple pregnancies in 123 ART babies. It was found that ART babies in comparison to normal babies have higher rates of mortality and abnormalities and lower birth weight.

Reference: Özer, E. A., Türko?lu E., Ball?, T., Sütçüo?, S., Erdemir, A., Co?ar, H., Kahramaner, Z., Kan?k, A., Men, G., Yaprak, I., Neonatal mortality and short term prognosis in newborns born after assisted reproductive techniques. Turk Arch Pediatri (2011), 46, pp. 37-38.

3. Congenital abnormalities are conditions existing at birth, for example trisomy 21 and spina bifida. Trisomy 21 is an genetic abnormality where the chromosome 21 exists in three copies instead of the normal two. These children have a number of physical and mental symptoms collectively called Down's Syndrome. Spina bifida is a neural tube defect which occurs when the neural tube fails to close at the caudal end during embryonic development. There are several subclasses of spina bifida. For example spina bifida cystica and spina bifida occulta. In spina bifida cystica either the meninges only herniate through the opening of the spinal canal (meningocele) or the spinal cord as well (myelomeningocele). These herniations do not occur in spina bifida occulta and it is therefore less severe.

--Z3279511 20:18, 2 August 2011 (EST)

Lab 2: Assessment

The capacitated spermatozoa binds to the zona pellucida glycoprotein 3 (ZP 3). ZP 3 functions as receptor and induces the acrosome reaction. In the acrosome reaction the spermatozoa releases enzymes from the acrosome which facilitate the penetration of the zona pellucida. ZP 2 acts as second spermatozoa receptor. Once membrane fusion occurs, where the spermatozoa and oocyte membranes fuse allowing the sperm nuclei to enter into the oocytes cytoplasm, membrane depolarization functions to prevent polyspermy. This is facilitated by enzymes that alter ZP3, which in turn will no longer bind to spermatozoa.

--Z3279511 12:38, 4 August 2011 (EST) --z3279511 15:38, 4 August 2011 (EST)

--Z3279511 12:17, 11 August 2011 (EST)

Differentially expressed RefSeq genes in human trisomy 21.jpg

--Z3279511 13:02, 11 August 2011 (EST)

Lab 3: Assessment

1. An important maternal dietary requirement for neural development is foliate. The incident of spina bifida and anencephali became much less since foliate is a component of the normal diet in Australia. Another maternal dietary requirement, particular in late neural development, is iodine. It is for the prevention of congenital hypothyrodism.

2. Facial manifestations of patient with DiGeorge Syndrome

Facial manifestations of patient with DiGeorge Syndrome.jpg

File:Facial manifestations of patient with DiGeorge Syndrome

--z3279511 21:00, 17 August 2011 (EST)

--z3279511 11:21, 18 August 2011 (EST)

Lab 4: Assessment

1. The allantois is an invagination of endoderm and surrounding extra-embryonic mesoderm into the connecting stalk. It forms an extension of the yolk sac into the connecting stalk (umbilical cord). In the human fetus, the fetal bladder is connected to the allantois via the urachus, which aids as passage for nitrogenous waist from the bladder.

2. The three vascular shunts are:

1) Ductus venosus: it connects the portal and umbilical vein to the inferior vena cava

2) Foramen ovale: it connects the right and the left atrium

3) Ductus arteriosus: it connects the left pulmonary artery with the arch of the aorta

3. Group project plan - DiGeorge Syndrome: I will be working on the following:

1) Clinical manifestation and explanations of these

2) Treatment options

3) Drawing of images

The distribution of the tasks to the individual group members can be found on the group discussion page under project plan. --Anna Marx 16:09, 21 August 2011 (EST)

--Anna Marx 11:18, 25 August 2011 (EST)

Lab 5: Assessment

Diaphragmatic hernia occur if there is a failure in closure of the peusoperitoneal foramen, which separates the thoracic cavity from that abdominal cavity.The most common diaphragmatic hernia occurs on the left hand side. During development in the embryo the right pleuroperitoneal folds closes before the left and the left is more prone to fail to close completely.In the even of a diaphragmatic hernia abdominal organs can move up into the thoracic cavity.--Anna Marx 10:55, 1 September 2011 (EST)

--Anna Marx 12:45, 1 September 2011 (EST)

Lab 6: Assessment

1) The palatal shelves fuse in week 9 of human development. The preparation process for this in the early embryonic development is growth, elevation, and fusion of palatal shelves.

2) The quail-chick chimera helps to study the neural crest origin and migration.

3) Tetralogy of Fallot is an abnormality that results the failure of neural crest cells to migrate into the cardiac outflow tract.

Lab 7 Attendance: --Anna Marx 12:05, 15 September 2011 (EST)

Lab 7: Assessmaent

Peer review for trisomy 21

INTRODUCTION: An introduction is a brief summary of the content of the page, should only contain information that will be discussed in more detail below and not be confusing. Furthermore it should raise the interest to keep on reading. This introduction did not have this effect for me. Try to explain what trisomy 21 is about, what the characteristics are and quickly introduce the sections that will be talked about on this page. Trisomy 21 is a very common condition and we have all seen people with it on the street, it would be nice to have a picture of a person with trisomy 21 for recognition. They are lovely people and it would engage the reader. The image "Chromosome- trisomy" is a repetition of the image "Trisomy 21 (Down Syndrome) Karyotypes" and fits much better in an "etiology/pathogenesis" section, which I am hoping to find below. Links to websites with further information or to a glossary are great when they are actually directly related to the section and relevant to it. However, the introduction is rather an invitation to read more on the actual page, where the content will be discussed in detail and where links to external pages and to the glossary can be used for further information. The text itself needs proper referencing (1st and 3rd paragraph).

SOME RECENT FINDINGS: The title "recent findings" would be more appropriate under the assumption that the most recent and most relevant research is discussed here. Recent findings should rather be placed in the end of the project. The image "Trisomy 21 newborn" has no copyright information and has also no relation to this section. It neither has to do with the recent findings discussed nor is it mentioned or referred to in the text.

TRISOMY 21 (DONW SYNDROME) KARYOTYPES: The image a good illustration of what the genetic difference of an individual with trisomy 21 and a normal person is. However it could be explained more in detail. First of all if "Karyotypes" appears in the title, it should as well be explained directly in the section and not via a link to an external glossary. Secondly it would be nice to see an etiology/pathogenesis section on the page. Some one who is interested in finding out more about trisomy 21 would want to know how it is caused, what the risk factors are (eg.: the age of the mother plays and important role), and how it happens, that the genes do not separate. A suggestion would be to make an etiology/pathogenesis section and to discuss the "Trisomy 21 karyotypes" and "Meiosis I and Meiosis II" in this section. Additioinally, in the introduction it has been explained that trisomy 21 and Down's syndrome are two names for the same abnormality. Hence from that point on chose one of the names and stick with it rather that mixing them up or having the both in the same heading. The spelling in the heading is wrong (Down Syndrome, should be Down's Syndrome).

ASSOCIATED CONGENITAL ABNORMALITIES: The associated congenital abnormalities are important because they have an impact on the life of individuals with trisomy 21. Hence the section could be a little more complex. It might be worth writing an introducing paragraph, in which the most common associated abnormalities and the prevalence is mentioned. Not to forget, that the clinical picture of trisomy 21 individuals varies highly. For example there is a person that even made it into university while in more severe cases individuals only speak a few words lifelong - some individuals present with congenital heart defects some have perfectly normal hearts and no problems lifelong, etc. May be each of the relevant abnormalities could be explained in a table as under "limb defects".

AMERICAN COLLEGE: Instead of this section it would be nice to see a "diagnostic test" section. In this the "ACOG" could be incorporated as external link. The tests mentioned here for example: measuring features of the back of the neck and ultrasound are not diagnostic test for trisomy 21. Trisomy 21 is detected by sampling the amniotic fluid and by genetic testing. Abnormalities of the back of the neck and ultrasound are techniques to detect other abnormalities. Hence these are not directly relevant to trisomy 21. I have noticed that there is a complex section about screening - which discusses the detection of trisomy 21 somewhat. However I find it a little confusing. A table is a good idea but maternal age is not a procedure and what are all the tests for? Trisomy 21? How do they work? A diagram is as well and excellent idea but what does it all mean? How is a buccal swap done? And again is that all relevant to trisomy 21? If I was for example a pregnant woman with the concern that my baby has trisomy 21, I would like to know what the commonly used test is, how it is done, what the risk factors are and how accurate it is.

PREVALENCE these section would be more appropriate after the introduction, may be as "epidemiology" section. Furthermore it would be interesting the see some figures that are more recent and worldwide.

SCREENING: See comment under AMERICAN COLLEGE. Also about "SCREENING BY COUNTRY" One sentence does not need and extra heading. Either this information is not important or there could perhaps be some more information about other countries as well and about the difference such an screening makes.

MEIOSIS I AND MEIOSIS II: See comment under TRISOMY 21 (DONW SYNDROME) KARYOTYPES ANEUPLOIDY: Aneuploidy has been explained before and this section has as such no relevance to the topic.

GROWTH CHARTS: May be this information could be presented under "Clinical presentation". From this section on its own I cannot derive weather children with trisomy 21 show abnormalities in growth or not and why it should be relevant.

REFERENCES: The first part of the references does not have a subheading but the rest does. May be it could be structured a bid differently. The first part contains articles, so why is it not under articles?

TERMS: It would be good to have a more terms in the glossary. Basically all words used in the sections above that would be new to a person with no scientific background should be explained here.


  • You have already collected lot's of the information needed, the page just need good structuring, and try to make sure that information is relevant to the topic.
  • The images "Chromosome- trisomy", "Trisomy 21 newborn", "Trisomy 21 (Down Syndrome) Karyotypes", "Human idiogram-chromosome 21" "Trisomy 21 hand features", and "John Langdon Down (1828 – 1896) was a British physician who in 1866 was first to describe the syndrome." have no copyright information.
  • An Idea: The 2009 Tropfest winner was Genevieve Clay with the short movie "My brother". This is a very sweet movie, which describes the personality of a person with trisomy 21 better than words can do. May be you like to integrate a link to the youtube video ( on you page. I am not sure if it is appropriate though.