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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)

Lab Attendence

--Z3332183 12:57, 28 July 2011 (EST)

--Z3332183 13:02, 4 August 2011 (EST)

--Z3332183 11:09, 11 August 2011 (EST)

--z3332183 11:03, 25 August 2011 (EST)

--z3332183 11:09, 1 September 2011 (EST)

--z3332183 11:50, 15 September 2011 (EST)

--z3332183 10:09, 22 September 2011 (EST)

Lab Assessment 1:

1. Identify the origin of In Vitro Fertilisation and the 2010 Nobel Prize winner associated with this technique

Robert G. Edwards was awarded the Nobel Prize for his work in the development of in vitro fertilisation. His work in this area first began when he realised that a possible method for treating infertility would be for fertilisation to occur outside of the body. Edwards worked towards finding methods to fertilise human egg cells outside of the womb, since previous experiments had been performed showing that rabbits egg cells could be fertilised in test tubes and result in offspring.

A human egg was first successfully fertilised in a test tube in 1969, although the egg was not able to develop beyond single cell division. Edwards then worked together with Patrick Steptoe, who used the laparoscope to inspect and remove eggs from the ovaries. These mature eggs that were removed from the ovaries and fertilised with sperm were able to divide several times.

On the 25th July, 1978, Louise Brown, the first IVF produced baby was born. In Australia, the first successful case of IVF was in 1980, and since then, the use of IVF as a fertility treatment has become more and more popular with 1, 596 IVF babies being born in 2005.

2. Identify a recent paper on fertilisation and describe its key findings

Not all sperm are equal: functional mitochondria characterize a subpopulation of human sperm with better fertilization potential.

•This article describes a study in which fluorescence microscopy was used to assess mitochondrial function of human sperm samples and to determine whether there was a link between mitochondrial function and the functional properties of individual sperm.

•It was found that mitochondrial activity did have a link to the quality of sperm both within different human samples as well as within the same sample.

•The sperm with more active mitochondria were found to contain a lower percentage of chromatin damage, as well as a greater ability to decondense and contribute to early development.

•The activity of mitochondria can be seen as a clear sign of the functionality of individual human sperm. In terms of practicality for fertilisation, cell sorting to produce a subpopulation based on mitochondrial activity and therefore sperm functionality may be possible.

Reference: Sousa, Ana Paula., et al. Not all sperm are equal: functional mitochondria characterize a subpopulation of human sperm with better fertilization potential. PLoS ONE. 6(3):e18112, 2011. [1]

3. Identify 2 congenital anomalies

Klinefelter syndrome

Larsen syndrome

Lab Assessment 2

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

The ZP protein that spermatozoa binds to is the ZP3 protein. After this binding has occurred, the acrosome releases degradative enzymes which allow the sperm to penetrate the zona pellucida.

2. Identify a review and a research article related to your group topic.

Review Article:The genomic basis of the Williams – Beuren syndrome •Williams syndrome is a genomic disorder with symptoms including mental retardation, visuospatial impairment & overfriendliness.

•It is caused due to a hemizygous contiguous gene deletion with regards to chromosome 7q11.23.

•This review article deals with the genomic assembly of the region involved in Williams syndrome as well as the chromosomal mechanisms such as deletions and duplications and the consequences of these.

Reference: Schubert, C. The genomic basis of the Williams – Beuren syndrome. Cell, Mol. Life Sci. 66:1178-1197, 2009 [2]

Research Article: Functional, structural and metabolic abnormalities of the hippocampl formation in Williams syndrome •In this study, neuroimaging (PET and fMRI) was used to investigate the hippocampal structure, function and metabolic integrity of 12 people with Williams syndrome compared to 12 healthy controls.

•N-acetul aspartate can be seen as a marker for synaptic activity and measures of this were reduced in those with Williams syndrome

•Although regular hippocampal size was maintained in both groups, slight changes in the shape were present.

•Through the results of the investigation, it was suggested that the neurocognitive abnormalities seen in Williams syndrome may be partly due to hippocampal dysfunction.

Reference: Meyer-Lindenberg A., et al. Functional, structural and metabolic abnormalities of the hippocampal formation in Williams syndrome. J Clin Invest. 115(7):1888-95, 2005 [3]

Lab Assessment 3

Differentially expressed RefSeq genes in human trisomy 21

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

Though there are a number of maternal dietary requirements, iodine is particularly important for late neural development. This is because iodine helps to prevent iodine deficient disorders such as hypothyroidism. Omega 3 is also important for neural development, particularly brain stem development.

2. Upload a picture relating to you group project. Breakpoint identification in individuals with deletions in the WS region and atypical phenotypes.jpg

Lab Assessment 4

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

The allantois is continuous with hindgut.

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

•Foramen ovale: is located between the right and left atria

•Ductus arteriosus: is located between the pulmonary artery and the aortic arch

•Ductus venosus: is located between umbilical vein and the inferior vena cava

3. Identify the Group project sub-section that you will be researching. etiology and diagnosis


2.History of the disease

3.Etiology *

4.Genetic Factors

5.Physical Characteristics

6.Associated medical conditions

7.Cognitive, Behavioural and Neurological Problems



10.Specialized Facilities/ supportive associations

11.Case studies

12.Interesting facts

13.Current research and developments

Lab Assessment 5

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

The left side is more likely to be the site of hernias as the right side of the diaphragm closes first during development, makeing the left side more susceptible to herniation.

Lab Assessment 6

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

During week 9 of development, the palatal shelves fuse. The secondary palates as well as the primary palate both fuse together during this period.

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

The early animal model that helped to elucidate the neural crest origin and migration of neural crest cells is the chicken model.

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

The abnormality that results from neural crest not migrating into the cardiac outflow tract is Tetralogy of Fallot.

Lab Assessment 7

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

Satellite cells are generally involved in muscle hypertrophy but they are not essential for muscle hypertrophy.

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

Chronic low frequency stimulation involves exposing fast muscles to the actions of low frequency muscles similar to the stimulation that the slow fibre type muscles are exposed to via slow motoneurons. This causes changes in the myosin heavy chain expression which results in a fast to slow fibre type shift in a “neighbour rule” sequence.

Peer Assessment of the Trisomy 21 Page

•The links in the introduction to further information regarding genetic and diagnostic links were useful, and they are in a good position on the page.

•In terms of the subheadings, the order does not have a very good flow about it. I think that the recent findings subheading should be further down towards the end of the page, not straight under the introduction before any elaboration on the causes or characteristics of Trisomy 21 have been provided.

•There is a good balance between pictures and information, though some of the pictures, in particular the graphs are not incorporated into the written information or explained very well in any detail.

•There also seems to be information missing in terms of important areas that should be explored in greater detail throughout the page. This includes information regarding aspects such as symptoms and characteristics of the abnormality, maybe a bit more on the history and discovery of the abnormality and some future research or directions regarding the disorder.


•Do not all have captions underneath them – for instance the first picture in the introduction section

•They do not all have the copyright information relating to free access included – regarding the image of John Langdon Down. Also this image does not relate to the information that it is placed near. It would be more relevant to have it in a section such as history of the abnormality. The image is also in the middle of 2 subheadings, and looks as it is not placed in the correct position.


•The terms or glossary list is below the references, where it should be just above them

•Reference number 6 is not formatted correctly – there is just a link with no other information

Lab Assessment 8: Peer Review

Group Project 9: Practise Formatting

Gene Normal Function Relation to Williams Syndrome
Elastin (ELN) Elastin is a main component of elastic fibres. It also contributes to the structure of connective tissue, particularly its flexibility and strength. The loss of one copy of this gene reduces the normal production of elastin by half.

Elastin haploinsufficiency is responsible for a number of abnormalities characteristic of Williams Syndrome, particularly connective tissue abnormalities and cardiovascular disease including arterial stenosis. [PMID: 20425789].

LIM domain kinase 1 (LIMK1) Studies, such as Wang et al in 1998 [PMID: 9685409] suggest that LIMK1 is involved in the area of the brain that is in control of the visualisation of an object as a set of parts.

It has also been implicated in other visual tasks such as drawing, making models and writing.

Studies differ in regards to the contribution of LIMK1 deletions to the phenotype expressed in Williams syndrome. Some studies have suggested that the loss of this gene leads to the problems with visuo-spatial tasks that are common in Williams syndrome. Other studies suggest that it is involved with the characteristic progressive loss of hearing, [PMID: 21655442] while other studies have not found these connections.
General transcription factor IIi (GTF2I This gene is involved in the production of the following two proteins:

• BAP-135: involved in the normal function of the immune system • TFII-I: helps in the regulation of other genes activity and is therefore active in many tissues of the body, particularly in the brain.

It has been suggested that the loss of one copy of this gene may be responsible for the intellectual disability seen in Williams syndrome. It may also be involved in the social characteristics of those with Williams syndrome.