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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)


--z3060621 10:55, 6 October 2011 (EST)

--z3060621 11:09, 29 September 2011 (EST)

--z3060621 11:42, 22 September 2011 (EST)

--Z3060621 12:56, 28 July 2011 (EST)

--z3060621 12:55, 4 August 2011 (EST)

--z3060621 11:39, 11 August 2011 (EST)

--z3060621 11:18, 18 August 2011 (EST)

--z3060621 11:05, 25 August 2011 (EST)

--z3060621 11:28, 1 September 2011 (EST)


1. Identify the origin of In Vitro Fertilization and the 2010 nobel prize winner associated with this technique.

Robert G. Edwards, a British scientist

2. Identify a recent paper on fertilisation and describe its key findings. A recent Swedish study published in the July issue 2011 of the medical journal Pediatrics, babies conceived via In Vitro Fertilization (IVF) are more likely to get various cancers by age 19 than when naturally conceived [1].

3. Identify 2 congenital anomalies.

- Hydrocephalus - cleft palate/lip

--Mark Hill 00:38, 30 July 2011 (EST) You need to cite the reference correctly for question 2.


1. Identify the ZP protein that spermatozoa binds and how is this changed (altered) after fertilisation.

ZP3 is a glycoprotein sperm receptor molecule in the zona which is one of three glycoproteins composing the zona pellucida. As a result of this binding, the acrosome is induced to release degradative enzymes that allow the sperm to penetrate the zona pellucida [2].

2. Identify a review and a research article related to your group topic. (Paste on both group discussion page with signature and on your own page)

Turner's Syndrome: New England Journal of Medicine by Virginia P. Sybert, M.D., and Elizabeth McCauley, Ph.D. Issue 351 Page 1227-1238 September 16, 2004.


1. What is the maternal dietary requirement for late neural development?

Iodine is essential for the developing brain of the fetus [3].

2. Upload a picture relating to you group project. Add to both the Group discussion and your online assessment page. Image must be renamed appropriately, citation on "Summary" window with link to original paper and copyright information. As outlined in the Practical class tutorial.

red blood cell of a thalassemia patient


1. The allantois, identified in the placental cord, is continuous with what anatomical structure?

The allantaois is continuous with the bladder [1].

2. Identify the 3 vascular shunts, and their location, in the embryonic circulation.

The three vascular shunts in the embryonic circulation include the following: ductus venosus develops within the liver, oval foramen between the atria and ductus arteriosus is the distal part of the left sixth pharyngeal arch artery passing from the left pulmonary artery to the dorsal aorta [2].

3. Identify the Group project sub-section that you will be researching. (Add to project page and your individual assessment page)

The sub-sections I will be researching in are etiology and clinical manifestation.


1. Which side (L/R) is most common for diaphragmatic hernia and why?

The most common side for diaphragmatic hernia is the left side because the pericardioperitoneal canal is larger than the right and closes later. Diaphragmatic is caused by a mutation in the gene that directs pulmonary development hence the left side would be more common as it seals off the pleural cavity at a later stage of development [3].


1. What week of development do the palatal shelves fuse?

At the end of the 7th week, the palatal shelves rotate rapidly upward into a horizontal position and then fuse with each other and with the primary palate to form the secondary palate[4].

2. What animal model helped elucidate the neural crest origin and migration of cells?

Mouse mutants provide information about mechanisms of neural crest migration and developmental restrictions[5].

3. What abnormality results from neural crest not migrating into the cardiac outflow tract?

It causes the incomplete conotruncal septation. Ablation of cardiac neural crest cells causes persistent truncus arteriosus, tricuspid stenosis, ventricular septal defects, transposition of the great vessels, double outlet right ventricle, and tetralogy of Fallot[6].


1. Are satellite cells (a) necessary for muscle hypertrophy and (b) generally involved in hypertrophy?

a) Satellite cells are not necessary for muscle hypertrophy.

Muscle development occurs in the embryo through the formation of myoblasts, which undergo extensive proliferation to form terminally differentiated, postmitotic myocytes. Myocytes express Actin, Myosin, and other contractile proteins and fuse to form contractile myofibrils.

Striated muscle development involves both prenatal and postnatal events: primary myogenesis (occurs during the stage of the embryo) and secondary myogenesis (occurs during the stage of the fetus) lay down the muscular system, and satellite cells act in muscle growth postnatally.

b) Satellite cells act in muscle growth postnatally and in response to exercise or muscle damage.

Postnatal muscle growth involves satellite cells, small quiescent cells underlying the basal lamina of the muscle fiber. In response to exercise or muscle damage, satellite cells form myocytes, which permit further muscle growth. The satellite cells in the trunk and limb also arise from the somites[7] .

2. Why does chronic low frequency stimulation cause a fast to slow fibre type shift?

That fast-to-slow fibre-type transitions are associated with increases in satellite cell activation, content and fusion to transforming fibres. The higher myonuclear content is a prerequisite for fast-to-slow fibre-type transitions, and that satellite cells play an important role in this adaptive response.

In the presence of a viable satellite cell population, CLFS is known to induce increases in satellite cell content and activity, and large fast-to-slow phenotypic changes[8].

Peer Assessment Trisomy 21

  • the layout of the graphs and images were not consistent
  • overall an okay wiki page



Group 2

  • interesting layout
  • pictures were good examples
  • maybe need a touch up with the referencing
  • i liked it how it was worded in a way that could be understood for a wide audience however the structure and format could not be read so easily

Group 3

  • a lot of writing and so makes the wikipage interesting to read
  • the image in the pathogenesis section needs fixing
  • the image layout is not organised well
  • needed to explain Klinefelter's disorder in simple terms. I could understand it but if it was explained in a more simple way it would be much better.

Group 4

  • Organised well
  • Subheadings in the epidemiology section not in the centre of table
  • images in the current/future research section is disorganised
  • a lot of referencing was done and maybe not necessary
  • choice of pictures were good examples

Group 5

  • the layout was not well structured
  • was able to understand the disorder

Group 6

  • really well done
  • format and structure of the wikipage was consistent throughout

Group 7

  • could not understand the pathogenesis of the disease that well
  • was difficult to understand maybe because of the use of the technical wordings

Group 8

  • good wikipage
  • was able to understand it

Group 9

  • interesting
  • a lot of information has been put into it but relevant and not repetive

Group 10

  • struture and format done well
  • easy to read

Group 11

  • interesting pictures
  • overall done well


1. Besides fetal alcohol syndrome, identify another environmental teratogen that can lead to hearing loss.

Isotretinoin embryopathy

2. Identify 3 factors that contribute to poor neonatal drainage of the middle ear.

Mucocillary clearance, pumping action of Eustachian tube, presence of intraluminal surface tension[9].

3. Identify 1 genetic abnormality that affects hearing development and link to the OMIM record. (Your individual abnormality should be different from all other students)

276900 (MIM number) USHER SYNDROME, TYPE I; USH1[10].


1. Name the components that give rise to the interatrial septum and the passages that connect the right and left atria.

The components that give rise to the interatrial septum are the septum primum and septum secundum. Septum primum forms on the ceiling of the right atrium, just adjacent and to the right of septum primum is the septum secundum a thick and muscular, in contrast to the thin septum primum. The edge of the septum secundum grows cranial-caudally and ventral-dorsally, but it halts before it reaches the atrioventricular septum.

The passages that connect the right and left atria are the foramen ovale and the foamen scundum. Blood shunts from the right atrium to the left atrium passes through two staggered openings: the foramen ovale near the floor of the right atrium, and the foramen secundum near the roof of the left atrium. This arrangement allows blood to flow from the right atrium to the left atrium, but not in the reverse direction, as the thin septum primum collapses against the stiff septum secundum, effectively blocking blood flow back into the right atrium[11].

2.Identify the cardiac defects that arise through abnormal development of the outflow tract.

Persistent truncus arteriosus and ventricular septal defects. Persistent TA results from failure of the truncal ridges and aorticopulmonary septum to develop normally and divide the TA into the aorta and pulmonary trunk. Aorticopulmonary septal defect is a rare condition in which there is an opening (aortic window) between the aorta and pulmonary trunk near the aortic valve[12].


  1. Moore, K.L. & Persuad, T.V.N. (2008). The Developing Human: clinically oriented embryology (8th ed.). Philadelphia: Saunders.
  2. Moore, K.L. & Persuad, T.V.N. (2008). The Developing Human: clinically oriented embryology (8th ed.). Philadelphia: Saunders.
  11. Schoenwolf, G.C., Bleyl, S.B., Brauer, P.R. and Francis-West, P.H. (2009). Larsen’s Human Embryology (4th ed.). New York; Edinburgh: Churchill Livingstone
  12. Moore, K.L. & Persuad, T.V.N. (2008). The Developing Human: clinically oriented embryology (8th ed.). Philadelphia: Saunders