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'''Lab Attendance:'''
'''Lab Attendance:'''
'''Questions and Answers for Lab Assessment 7'''
'''Questions and Answers for Lab Assessment 7'''

Revision as of 16:46, 12 September 2011

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)

--Z3289991 12:55, 28 July 2011 (EST)

Questions and Answers to Lab Assessment 1

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

1. In vitro fertilization originated from the American doctor John Rock’s extraction of an intact fertilized egg. Since IVF (In Vitro Fertilization) involves the artificial insemination of sperm and eggs outside of the body, John Rock’s method paved the way of IVF clinics coming into practice (Gladwell, 2000). The first pregnancy which began off as successful using IVF was reported in the Lancet medical journal by scientists from the Australian Monash University (IVF, 2011). Unfortunately, the pregnancy did not progress any further as the embryo failed to implant properly in the uterine wall. This occurred in 1973. Robert Edwards, who was the 2010 Nobel Prize winner (Committee, 2010), carried out the successful insemination of a sperm and egg outside of the body which led to the healthy birth of a newborn in 1978 (News, 2011). Embryos can now be successfully frozen and transferred from embryonic donors to acceptors.

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

2. In 2010, a study was done into finding a therapy for allowing fertilization to occur even when there was sperm centrosomal dysfunction. Reproductive technologies will be invented in the coming years to analyse sperm centrosomal function and counter sperm centrosomal dysfunction. These reproductive technologies will be referred to as assisted reproductive technologies (ART). These technologies are necessary since the sperm centrosome was found to play an important role in the fertilization process after the intracytoplasmic sperm injections (ICSI). This all occurs within the cytoplasm of the oocyte. The answer was sourced from the single reference, (Yukihiro Terada, 2010), details of which can be found in the reference list.

3. Identify 2 congenital anomalies.

4. Two distinct congenital anomalies are amniotic band syndrome and atrial septal defect. Amniotic band syndrome is a limb anomaly which is caused by foetal parts such as limbs of the foetus being stuck in amniotic fibrous bands whilst the baby is in utero. Two main theories have been brought forward to explain how it is caused. The amniotic band theory suggests that there was partial rupture of the amniotic sac (Rapini, Bolognia, & Jorizzo, 2007). However, the chorion remains stable. Hence, fibrous bands of the ruptured ammonium float in fluid and entrap the limbs. The second theory suggests that there may have been vascular disruption to the foetus whilst in utero. Atrial septal defect is a congenital anomaly of the heart. It enables blood flow between the left and right atria via the inter arterial septum (Ira H Gessner, 2008). Thus, there is a mix of venous and arterial blood. This can be clinically significant, depending on how bad the defect is due to mixing oxygenated blood with deoxygenated blood.


Committee, N. P. (2010). The Nobel Prize in Physiology or Medicine 2010. Retrieved July 30, 2011, from Nobel Prize: http://nobelprize.org/nobel_prizes/medicine/laureates/2010/press.html

Gladwell, M. (2000, October 3rd ). John Rock's Error. The New Yorker . New York, New York, America.

Ira H Gessner, M. (2008). Ostium Secundum Atrial Septal Defects. Retrieved July 30, 2011, from Medscape Reference: http://emedicine.medscape.com/article/890991-overview

IVF, M. U. (2011). History of IVF. Retrieved July 30, 2011, from Monash IVF- Life Starts Here: http://www.monashivf.com/About_Monash_IVF/History_of_IVF.aspx

News, B. (2011). On This Day. Retrieved July 30, 2011, from BBC News: http://news.bbc.co.uk/onthisday/hi/dates/stories/july/25/newsid_2499000/2499411.stm

Rapini, R. P., Bolognia, J. L., & Jorizzo, J. L. (2007). Dermatology: 2-Volume Set. St. Louis: Mosby.

Yukihiro Terada, G. S. (2010). Essential Roles of the Sperm centrosome in human fertilization: Developing the therapy for fertilization failure due to sperm centrosomal dysfunction. Journal of Experimental Medicine , 247-258.

--Z3289991 09:02, 3 August 2011 (EST)

--Mark Hill 09:47, 3 August 2011 (EST) A very complete answer to all 3 questions, well done.

--z3289991 11:23, 4 August 2011 (EST)

Lab Assessment 2 Questions and Answers

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

1. ZP-3 (Zona pellucida sperm binding protein-3) is a protein which is coded for by the ZP3 gene. It is the receptor in the zona pellucida which binds with sperm at the beginning of fertilization. The protein encoded by this gene is a major structural component of the zona pellcida and functions in the primary binding and stimulation of the sperm acrosome reaction. Typically, the acrosome reaction will not occur until the sperm comes into contact with the jelly layer of the oocyte. After the jelly layer has been penetrated, the acrosomal enzymes will dissolve and the actin filaments will contact the zona pellucida. A signalling cascade will happen as the calcium influx occurred. ZP3 will not bind sperm to the membrane after this and it will now act to block polyspermy.

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)

2. See main group assessment page, group 3, as well as below:

Below is a review article:

It is entitled: Termination Rates After Prenatal Diagnosis of Down Syndrome, Spina Bifida, Anencephaly, and Turner and Klinefelter Syndromes: A Systematic Literature Review


The Research Article:

It is entitled: Prenatal and Postnatal Prevalence of Klinefelter Syndrome: A National Registry Study


Both articles explore more the epidemiology of klinefelter's syndrome as I felt that it would be interesting to look at its prevalence, and frequency of distribution within a population. The first review article that I hasve linked to explores the frequency of Klinefelter's syndrome in a population along with various other genetic anomalies.

--z3289991 06:22, 9 August 2011 (EST)

Date Stamp: --z3289991 11:07, 11 August 2011 (EST)

Questions and Answers for Lab Assessment 3

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

1. Iodine is very important in preventing late stage neural tube defects. Many defects have arisen from neural tube defects in the past, such as Iniencephaly, which is where the head is bent quite severely towards the spine. Usually, the infant lacks a neck and doesn't survive for more than a few hours. Another neural tube defect that can arise is Hydranencephaly, whereby the cerebral hemispheres are missing and are full with sacs of cerebrospinal fluid (CSF). It prevents cretinism if taken properly.

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.


Klinefelter's Syndrome patient testicular sample

Differentially expressed RefSeq genes in human trisomy 21

Date Stamp:--Robert Klein 11:08, 18 August 2011 (EST)

Questions and Answers for Lab Assessment 4

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

1. 1. The allantois is continuous with the endoderm andr hindgut of the embryo.

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

2. Three vascular shunts and their respective locations in the embryonic circulation are as follows: • Ductus venosus - Found between the umbilical view and the inferior vena cava of the heart • Ductus arteriosus - Found between the pulmonary artery and the descending aorta of the heart • Ductus arteriosus - Found between the pulmonary artery and the descending aorta of the heart

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

3. I will be researching Epidemiology, Similar defects and the Glossary of terms for Klinefelter's Syndrome.

Date and Time Stamp:--Robert Klein 11:17, 25 August 2011 (EST)

Questions and Answers for Lab Assessment 5

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

1. Around 90% of hernias of the diaphragm do occur on the left side, so it is the most common place for them to occur. This can be caused by uneven diaphragm closure during embryonic development, and the left side is supposed to close after the right side, therefore there is higher risk of herniation on the left side.

Dr Hill, I have completed my Project sections for the time being as you requested.Cheers --Robert Klein 06:06, 1 September 2011 (EST)

Lab Attendence:--Robert Klein 11:05, 1 September 2011 (EST)

Questions and Answers for Lab Assessment 6

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

1. Week 9 is when the palatal shelves usually fuse. The fusion of the palatal shelves is also referred to as the fusion of the secondary palate.

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

2. The early animal model used was quail chick chimeras, which are essentially quail chicks made of genetically distinct groups of cells. These were used in the 1980s to investigate neural crest migration. These organisms are appropriate for the purpose, since there are differences in the nucleoli of chicks and quail, so it was easy to see the migration of the neural crest cells in the organisms.

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

3.This is known as a 'Tetralogy of Fallot', and this can result in truncation or the complete absence of the outflow tract.

Lab Attendance:

Questions and Answers for Lab Assessment 7