From Embryology
Revision as of 20:44, 13 October 2010 by Z3252083 (talk | contribs) (Group Six)



--Mary Nicolas 23:38, 28 July 2010 (UTC)

--Mary Nicolas 23:37, 4 August 2010 (UTC)

--Mary Nicolas 23:52, 11 August 2010 (UTC)

--Mary Nicolas 23:39, 18 August 2010 (UTC)

--Mary Nicolas 23:31, 1 September 2010 (UTC)

--z3252083 23:52, 1 September 2010 (UTC)

--Mary Nicolas 23:31, 15 September 2010 (UTC)

--Mary Nicolas 00:00, 23 September 2010 (UTC)

--Mary Nicolas 23:36, 29 September 2010 (UTC)

Lab One Questions

Cell Division lecture

Fertization- First diploid cell



Early zygote.jpg

Lab Two Questions

1. Syncytiotropoblast cells secrete:

• Progesterone which maintains the integrity of the uterine lining.

• Human chorionic gonadotropin (hCG) which prevents the degeneration of the corpus luteum.

• Human placental lactogen (HPL) which modifies the metabolic state of the mother during pregnancy to facilitate the energy supply of the fetus

2. The corpus luteum secretes progesterone (signalled by hCG secreted by the trophoblast cells of the blastocyst) which consequently maintains the endometrium which provides an area rich in blood cells so that the zygote can develop.

Lab Three Questions

1. What Carnegie stages occur during week 3 and week 4?

Week 3: stages 7, 8 & 9

Week 4: stages 10, 11 & 12

2. What is the change in overall embryo size form the beginning of week 3 to the end of week 4?

2.6mm - 4.6mm (from 0.4mm in week 3 to 3-5mm in week 4)

3. Approximately when do the cranial (anterior) and caudal (posterior) neuropores close in the human embryo?

Cranial- stage 11 (days 23-26)

Caudal - stage 12 (days 26-30)

Oct4 staining on USSC-derived spheres,[1]

Lab Four Questions

1. Name the vessels that drain into the sinus venosus?

The vitelline vein, umbilical vein and the cardinal vein drain

2. What is the fate of the vitelline artery and vitelline vein?

The vitallene arteries contribute to the GI tract arteries; and the vitallene veins contribute to the adult portal system.

3. Name the 4 layers that constitute the placental barrier?



villi connective tissues

fetal capillary endothelium

4. What stem cells are found in abundance, and may be harvested from the placenta for therapeutic uses?

Haematopoetic stem cells

Lab Five Questions

1. What is the origin of the gastrointestinal tract smooth muscle?

Splanchnic mesoderm

2. At what Carnegie stage does the buccopharyngeal membrane begin to break down?

Carnegie stage 11

3. Identify the lung developmental stage in late embryonic to early fetal period.

Carnegie stage 22

4. In premature infant birth, which respiratory cell type may not have fully developed?

Pnuemocytes type 2/alveolar type 2 cells. These cells produce surfactant.

Lab Seven Questions

1. Briefly; what is a myotube and how is it formed?

Multinuclated undifferentiated sarcomere. Myoblasts undertake recurrent cell divison and then adhere together to form a myotube. The Nuclei of this myotube are positioned centrally within the muscle fibres.

2.What changes would I expect to see in the muscle fibre types in my legs if I:

a. Suffered a Spinal Cord Injury

• Lose it’s normal mosaic pattern; This is formed by the criss crossing of both type 1 (slow) and type ll (fast) fibres.

• [Over time] Predominately Type ll muscle fibres (glycotic fibres) are present in the paralysed leg.

b. Took Up Marathon running

• Slow twitch fibres proliferate due to their increased vasculature.

• Decrease in the amount of fast fibres.

Peer Assessment

Group One

This web page is very well set out. The information is clear and the subheadings are indicative of the historical development and the use of the ultrasound. I like the table format for the different types of ultrasounds as it provided a break from the text which in some parts seemed slightly superfluous. Overall this is an excellent webpage; it's educational value is high, it makes excellent use of external pages and it has an extensive glossary page which was greatly appreciated. Good job guys!!

Group Two

This web page is definitely one of my favorites. The information that you have provided is exceptional; the reference list is indicative of your extensive research. The table of deformities was a stand out for me as it was very well set out and was a effective break from the text. You also used excellent external links that were very well placed within the web page. A slight improvement would be to include a link or a reference to the brief time line where you state the names of the authors, and as previously mentioned, reference the statistics that you have included. Other than that, I applaud you for a job well done!

Group Three

I personally found the introduction to resemble that of an essay; I don't think an outline of what the webpage consists of is completely necessary seeing as there is a table of contents. A Glossary and proof reading are also needed. Other than that Your web page is great. The table of disorders that you have included is encompassing and simple enough to easily follow. It s a very well-rounded overview of Amniocentesis and I congratulate you on a job well done!

Group Four

Overall it is a good page. It's order muddled me up though. I think keep the History first then the procedure and so on an so forth. There are too few references which do not adequately support the claims that you make (not that I'm doubting you). You pictures are fantastic; as well as your table. The glossary is slightly short as there are some words that I had to google to find the meaning of. Other than that Good job guys!!

Group Six

There is A LOT of information. Although it is very well researched (to that I commend you), I personally think you need to break it up a bit. Maybe align the pictures differently; they are great pictures they just seem to hang there as a side thought. Maybe also include a table or flow chart for the procedure because it is quite hard to follow. Your glossary is adequate although your referencing may fall short in the screening test section. Great video to start off with!! Good work guys!!

Lab 10 questions

  1. Development of which endocrine organ is affected by low dietary iodine?

Low dietary iodine affects the development of the thyroid

  2. What are the effects of this deficiency on other non-endocrine system development?

Iodine deficiency in the mother may lead to muscarriage, still births and mental abnormalities in their offspring. Iodine deficiency in children may lead to them growing to be stunted, apathetic, mentally retarded and not be capeable of normal speech, hearing or movement.

  3. At approximately what week in development do many endocrine organs appear to begin their function?

10 weeks.

  1. <pubmed>20003538</pubmed>