From Embryology

Group 2

Chorionic Villus Sampling



Lab 1. here--z3265772 23:43, 28 July 2010 (UTC)

Lab 2. here--z3265772 22:57, 4 August 2010 (UTC)

Lab 3. here--z3265772 23:14, 11 August 2010 (UTC)

Lab 4. still here--z3265772 00:03, 19 August 2010 (UTC)

Lab 5. always here--z3265772 23:06, 25 August 2010 (UTC)

Lab 6. here--z3265772 23:54, 1 September 2010 (UTC)

Lab 7. here--z3265772 23:08, 15 September 2010 (UTC)

Lab 8. here--z3265772 23:13, 22 September 2010 (UTC)

Lab 9. here--z3265772 23:18, 29 September 2010 (UTC)

Lab 10. here--z3265772 22:05, 6 October 2010 (UTC)

Lab 11. here--z3265772 22:25, 13 October 2010 (UTC)

Lab 12. here for every lab :)--z3265772 22:17, 20 October 2010 (UTC)

Lab Questions

Lab 1 Questions

Complete tasks associated with the online individual and group assessments including:

1. Demonstrate the ability to create an attendance signature.

2. Create a subheading, link and add an image to student page.

learning to use page

internal link Cell division

external link SMH

lecture 2


Early zygote.jpg

Search Pubmed

Search Bookshelf Chorionic villus sampling

Search Pubmed Now: Chorionic villus sampling

3. Vote here (with student signature) for the major topic for the group project before Lab 2.

Lab 2 Questions

1. What factor do the synctiotrophoblast cells secrete to support the ongoing pregnancy?

Syncytiotrophoblasts secrete Human Chorionic Gonadotropin (hCG) hormone, which prevents degeneration of the corpus luteum

2. What does the corpus luteum secrete to prevent continuation of the menstrual cycle?

Oestrogen and Progesterone. Progesterone helps make the endometrial lining ready for implantation if an egg is fertilized. Progesterone also changes the endometrium to a secretory lining (from proliferative), which creates an ideal environment for the blastocyst.

Lab 3 Questions

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

Carnegie stages 7 (gastrulation and notochord formation) to 13 (Somite no. 21-29, caudal neuropore closes)

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

embryo has grown 2.6mm to 4.6mm. (week 4. 3mm to 5mm - week 3. 0.4mm)

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

Cranial neuropore closes at carnegie stage 11, which is 23-26 days

Caudal neuropore closes at carnegie stage 12-13, which is 26-30 days

Lab 4 Questions

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

the three venous inputs that drain into the sinus venosus are the vitelline vein, umbilical vein and common cardinal vein

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

Vitelline arteries - arises from dorsal aorta, contribute to adult GIT arteries, fuse to become superior mesenteric artery

Vitelline veins - empties into sinus venosus, contribute to the adult portal system

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

syncitiotrophoblast, cytotrophoblast, villi connective tissue and fetal capillary endothelium

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

hematopoietic stem cells

Lab 5 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.

Lung development, budding of lungs from the trachea, starts to occur in Carnegie stage 22

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

Pnuemocytes type 2 (or alveolar type 2 cells) which produce surfactant.

Lab 7 Questions

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

Myoblasts are single cells that differentiate to form myotube. The myotube is multiple nuclei all bound by a single membrane a developing muscle cell or fiber with a centrally-located nucleus. Thus, the myotubes must have been formed from the fusion of numerous myoblasts

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

a) Suffered a spinal cord injury:

Atrophy: Reduction of slow fibres (type I) and conversion to fast twitch fibres (type II)

b) Took up marathon running:

Muscles would conversion from fast twitch(type II) to slow twitch fibres(type 1)

Peer Review Task

Group 1: The layout is really easy to follow, everything seems to be in the right order and flow really well. i could easily follow what they had written. One thing i found especially impressive, was that they had taken the time to explain every image when you click on it. this would've taken a lot of time and effort that isn't immediately available to see, but helpful if you need to know more about the image, you just click on it. What could be improved: in one of the tables, under the heading minor signs of trisomies, pleuxs should be plexus. i didnt see any other spelling mistakes though. Also, it seems only one person has contributed most of the work, and there are three in the group. i found this to be the case for most pages.

Group 3: This project is very well written, and easy to follow. i loved the disorders section, with the table, graph and pictures it made it really easy to follow, and interesting! when you see a picture like the anencephaly one, it makes you stop and read what its about! I also like how many student drawn diagrams there are, they have really put in a lot of effort. I definitely learnt a lot from reading this page.

What could be improved: The ethics section has no references, also the current research section seems to be copied straight from the internet. there are also a few spelling mistakes in the ethics section - waranted=warranted, phsychological=psychological

Group 4: Felicias drawings are amazing! they go into so much detail and she has clearly put in so much effort in doing them! That was the first thing i noticed when looking at the page. I actually really like the overall feel of the page, and the bigger pictures help. The first two pictures really caught my attention and made me want to read all about PUBS. I did like all the dot points, because they made it a little easier to follow, but maybe a little simplistic.

Improvements: Under the sample analysis heading, they have put 'the' twice. just need to delete one. Under the disorders section, they have put that unlike PUBS, CVS and amniocentesis do test for neural tube defects. CVS doesnt test for neural tube defects, only amniocentesis. Alot of the page in not referenced. Other than that, awesome job!

Group 5: I liked the fact that everything is referenced, it made me feel like they have really researched what they have put on there. The page is very informative, if not a little simplistic, but i learnt alot about fetal fibronectin. i liked the student drawn diagram!

improvements: definitely extra pictures. If you cant find any that you can use, start emailing the companies, this is how i got most of our permissions, as i couldnt find any with permissions. as a last resort try wiki, all of their pictures arent copyright protected. Also, probably best to go through the criteria for the page, youve missed the history altogether. Here it is for you: project outline:

1. Intro

2. historic background

3. current associated research

4. simplified description of technique

5. student drawn figure or animation

6. reference list

7. glossary

8. external links

Group 6:

I like how the page is organised, its easy to follow and the layout was great. The pictures helped me with understanding the sections, although maybe they could be a bit bigger. I did learn alot about Maternal serum alpha-fetoprotein from this page, Thanks!

Improvements: Under the heading MSAFP testing and the community, there is a spelling mistake. liklihood should be likelihood, and servey should be survey. The page also looks a bit like an essay, maybe for some parts you could do a few tables to make it easier to follow

Lab 10 Questions

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


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

leads to neurological defects (cretinism) as thyroid is needed for neural development, hypothyroidism, low body weight, poor muscle tone, low body temperature.

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

At around week 10 most endocrine organs begin secreting hormones

Lab 12 Questions

1. During which trimester does fetal length change the most and when does fetal weight change the most?

Fetal length changes mostly in the second trimester, and fetal weight changes the most in the third trimester

2. What is the name of the theory that links postnatal health with prenatal development?

Fetal origins hypothesis

3. Which hormone initiates and maintains labour during birth and where does it come from?

Oxytocin from posterior pituitary