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'''Lab 10''' --[[User:Z3333427|Z3333427]] 09:48, 3 October 2012 (EST)
'''Lab 10''' --[[User:Z3333427|Z3333427]] 09:48, 3 October 2012 (EST)
'''Lab 11''' --[[User:Z3333427|Z3333427]] 09:56, 10 October 2012 (EST)


==Lab exercises==
==Lab exercises==

Revision as of 09:56, 10 October 2012

Lab attendance

Lab 1 --Z3333427 10:31, 25 July 2012 (EST)

Lab 2 --Z3333427 10:05, 1 August 2012 (EST)

Lab 3 --Z3333427 10:09, 8 August 2012 (EST)

Lab 4 --Z3333427 10:08, 15 August 2012 (EST)

Lab 5 --Z3333427 10:07, 22 August 2012 (EST)

Lab 6 --Z3333427 10:13, 29 August 2012 (EST)

Lab 7 --Z3333427 10:20, 12 September 2012 (EST)

Lab 9 --Z3333427 10:58, 26 September 2012 (EST)

Lab 10 --Z3333427 09:48, 3 October 2012 (EST)

Lab 11 --Z3333427 09:56, 10 October 2012 (EST)

Lab exercises

Lab 1

1) Identify the origin of In Vitro Fertilization and the 2010 nobel prize winner associated with this technique and add a correctly formatted link to the Nobel page.


Dating back to 1953, the first intact human fertilized egg was extracted by John Rock reported by the Australian Foxton School researchers to be only a transient biochemical pregnancy. The first pregnancy made possible by in vitro human fertilisation (IVF) was reported in 1973 by the Lancet from Monash University, however the pregnancy itself only lasted a small number of days. It was not until 1978 that the first child (Louise Brown) was born with the help of IVF. The process was carried out by Steptoe and Edward successfully the year before. IVF History


At the Nobel price ceremony in 2010, Robert Edwards, was awarded the price in Physiology or Medicine for his contribution in the field of human infertility and the development of IVF treatment. Nobelprize.org


2)Identify and add a PubMed reference link to a recent paper on fertilisation and describe its key findings (1-2 paragraphs).


<pubmed>22611166</pubmed>

Today's couples are delaying childbirth to later stages in life which in many cases translate into complications with childbirth. The aim of this study is to assess the extent in which factors related with IVF treatments contribute to anxiety levels and mental health a year after childbirth.

The couples included were either of singleton pregnancy (IVF treatment) and subfertile couples (naturally conceived). Parental trait anxiety (Dutch version of the Spielberger State-Trait Anxiety Inventory) and mental health (Dutch version of General Health Questionnaire) were assessed 1 year after childbirth.

A hundred and ninety-six couples participated, in which 93% were eligible. Trait anxiety and mental health were similar in both groups (IVF and naturally conceived). However, fathers who had naturally conceived children more often recorded mental health scores in the clinical range (21%) compared to the fathers who had undergone IVF (9%).

Females risk of having a trait anxiety or mental health score was lowered by having a greater number of IVF treatment cycles, whereas males risk had been lowered by being treated by IVF for a longer time period prior to pregnancy.

Therefore it was concluded that IVF treatment is not associated an increase in clinically relevant Spielberger State-Trait scores in parents 1 year after childbirth. This study also indicated that a higher number of IVF treatment cycles and an extended time to pregnancy were associated with better mental health.


Lab 2

Lab 2 Assessment

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Conjugate Sperm Pairs


Question 1:

Conjugate Sperm Pairs in American Opossums


(A) Paired and single sperm of the short-tailed opossum Monodelphis domestica.

(B) Pairs of conjugate sperm attached by the heads, the top pair starting to separate after capacitation.

(C) Pair of conjugate sperm separating.

(D) Electron microscopy of exquisite sperm head alignment in conjugate sperm pair (credit: Harry Moore). doi:10.1371/journal.pbio.0060130.g003

Citation: Pizzari T, Foster KR (2008) Sperm Sociality: Cooperation, Altruism, and Spite. PLoS Biol 6(5): e130. doi:10.1371/journal.pbio.0060130

Copyright: © 2008 Pizzari and Foster. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


Question 2:

L-selectin is a cell adhesion protein that is associated with the implantation process. The protein is found on lymphocytes and belongs to the selectin family of proteins and play an important part in lymphocyte-endothelial cell interactions. It has been discovered that the outer cell of the blastocyst express the protein L-selectin during the time the uterus becomes enriched with carbohydrates. L-selectin is known to briefly bind to carbohydrates and the sticking interaction between the two molecules allow the embryo's progress along the uterine wall to slow down.


A study on L-selectin discovered that during the time of implantation, the trophoblast which are found on the outer layer of the blastocyst are the molecules which expresses L-selectin. The expression of L-selecting by trophoblast occur just in time for the embryo to slow down and for pregnancy to take place.

<pubmed>22717627</pubmed>


Lab 3

question 1

The 'gestational age' is defined as approximately 14 days (2weeks) prior to fertilisation which is a measure of days dating back to the last menstrual cycle. This is clinically significant as the 'gestational age' is easier and more accurately determined before and after birth compared to the 'post fertilisation age' which measures the age since the fertilisation of the egg.

Although 'gestational age' is about 2 weeks greater than 'post fertilisation age' it is still more clinically significant as the exact date of fertilisation is difficult to determine.

Gestational and Post fertilisation age


question 2

3 types of tissues formed from myotomes include bone (sclerotome), dermis (dermatome), skeletal muscle (myotome).

Histological description of:

  • Bone (sclerotome)

- Bone is a specialised form of dense connective tissue which gives the skeleton the necessary rigidity. There are two histologically different type of bones:

Trabecular bone (spongy bone) which form a network consisting of branches of bars and sheets of bone. The opposite ends of long bones (epipyses)consist of trabeculae bone. It aids in the distribution of the load across the bone. Compact bone does not contain any macroscopically visible spaces or hollows. Compact bone mainly form the shaft (diaphysis) of long bones, and surrounds the marrow cavity. Compact bone aids in providing rigidity.

  • Dermis (dermatome)

-The dermis is a thick layer of connective tissue which is the underlying layer the epidermis is attached to. The deepest part of the dermis is lined by subcutaneous tissue without a clearly defined boundary. The dermis varies in thickness but is about 1-2 mm, and can be divided into two sublayers:

The papillary layer is made up of loose connective tissue, which has a great number of capillaries and tend to fill hollows at the boundary which it shares with the epidermis. The collagen fibres in the papillary layer appear finer relative to the reticular layer. The reticular layer is comparatively more dense and contains less cells than the papillary layer which it underlies.

  • skeletal muscle (myotome)

Skeletal muscle develop from mesoderm which occurs by the fusion event of mononucleated myoblast and the formation of mutinucleated myotubes that begin to express proteins which form sarcomeres within myofibers. Skeletal muscle fibres occur in bundles, which make up the muscle. The muscle is then surrounded by the epimysium (connective tissue). The surrounding connective tissue is continuous with the muscle fascia.

of the somites

Lab 4

question 1:

Chorionic villus sampling (CVS) is one of a number of invasive prenatal diagnostic techniques. The diagnosis involves acquiring a sample of the placenta, which is then used to obtain information for genetic abnormalities through testing in placental tissue. In order to collect a sample of the placenta which contain chorionic villi, a needle is inserted into the placental tissue. A large number of chromosomal abnormalities, including trisomy 13, trisomy 18, down syndrome and Turner syndrome can be detected by CVS. A great number of genetic disorders, such as cystic fibrosis, and sickle cell disease. CVS is only considered to be a safe diagnostic procedure before the 14th week of gestation, and is not used to look for all genetic disorders, but only the diseases which the embryo is at increased risk for based on parental genes. Chorionic Villus Sampling (CVS) <pubmed>22708335</pubmed>

Amniocentesis in an alternative prenatal diagnostic technique in which a sample of amniotic fluid (located in the amniotic cavity) is collected. A needle is inserted into the amniotic cavity by passing through the abdomen. The amniotic sac is located prior to the procedure to ensure that both the embryo and placenta is not disturbed during the procedure. Amniocentesis Amniocentesis is used to examine the presence of any infection, neural tube defects, lung maturity and can also perform genetic evaluation and chromosome analysis to test for chromosomal abnormalities such as down syndrome. <pubmed>22875501</pubmed>

question 2:

<pubmed>21939558</pubmed>

Mesenchymal stem cells (MSCs) are a potential source for stem cells used in transplantation which is proving to be an effective therapy for the treatment of stroke. The cell source is becoming important for clinical application due to the relative ease in obtaining MSCs and their great ability in proliferating. In this paper, the therapeutic potential of MSCs was determined by administering the stem cells intrathecally by lumbar puncture. MSCs derived from human umbilical cord was administered intrathecally into the lumbar spinal cord of a rat and investigating if the MSCs passed the blood brain barrier, continued to proliferate and whether or not it improved post-stroke neurological function recovery.

A greater number of cells were shown to migrate within the ischemic area when rats were receiving human umbilical cord blood-derived MSCs (hUCB-MSCs)intrathecally by lumbar puncture (LP) compared with rats receiving MSCs intravenously. Stem cells administered intrathecally survived and eventually differentiated in significant numbers into neurons and astrocytes. Motor function was greatly improved and there was significantly less ischemic damage in animals treated with hUCB-MSCs compared to animals used as a control (untreated).

It was concluded that intrathecal administration of MSCs by LP is effective in animals and based on such results may translate to therapeutic use in human treatment of injuries within the central nervous system such as stroke and neurodegenerative disorders.

<pubmed>21882426</pubmed>


Lab 7

question 1: Provide a one sentence definition of a muscle satellite cell (b) In one paragraph, briefly discuss two examples of when satellite cells are activated ? The muscle satellite cell is known to be the stem cell which resides in skeletal muscle, and supply myoblasts, enabling it to undergo repair, growth and homeostasis. Satellite cells are activated when skeletal muscle tissue is undergoing repair. Damaged skeletal muscle cells cannot be replaced by new muscle cells. As a result additional nuclei are obtained from muscle satellite cells. These stem cell then multiply and then act to fuse with damaged skeletal muscle fibres. Satellite cells are shown to be activated in response to extreme exercise, minimizing the effect of damages caused by tension and the process of necrosis. <pubmed>3693217</pubmed>

question 2: In one brief paragraph, describe what happens to skeletal muscle fibre type and size when the innervating motor nerve sustains long term damage such as in spinal cord injury? Experiments conducted in mice have shown that a long term damage in spinal cord often results in extreme atrophy of muscle fibres in which the cross sectional area of the muscle decreased substantially. In addition it was discovered that a sustained motor injury involved an alteration in skeletal muscle fibres which adapted an even larger number of Myosin heavy chain 2b. The muscle fibre begin to adopt a greater proportion of fast twitch muscle fibres as opposed to slow twitch muscle fibres. <pubmed>10484346</pubmed><pubmed>9755066</pubmed>

Lab 8

Vision project

The top image of the eyes is a great idea to introduce an audience to your topic. The copyright of the image is there along with the reference. However, the hand drawn image do not have a reference as to where you located the information for the diagram. The images further down the page which are referenced to a textbook had no copyright associated with it. It is important to make sure that the textbook is not protected by copyright laws before placing those images in your page. Referencing and copyright needs to be included in every image on the page, many of your images don't have the necessary information.

The information is easy to understand, however it is difficult to locate. Things seems to be out of place. Try not to include images on both side of the page, it is highly distracting as they alternate far too often. I also noticed that development and function were both under one heading. This made things a little confusing as the information between the two topics were shared in the same paragraph.

What I found to stand out were the historic images. These are a great addition to the page. Having said that, they're often difficult to understand and therefore explaining the images would be great. The history, current research and glossary sections all seem to be incomplete, these need to be worked on.

Something that i found to be really well explained was the developmental stages of the eye and associated structures. This is very important as the topic is about the development. Although the information for this section seems to be great, there seems to be a lack of references, it is important to cite where you derived the information from.

Overall the page seems to have the right information, however, just remember to include the right references, make your diagrams and labels more visible and try to organise your information into tables or dot points to make it easier to follow.

Somatosensory

The introduction for somatosensory is very informative and the overview of its development is great. The information is also great, however i do notice a bit of overlap throughout the page. It is important to go through the information and remove information that is repeated.

At times it feels like there is far too much information and not enough images, tables and diagrams. Dot points would be an alternative way to present your information as organisation is necessary. Including some tables and breaking up the texts into more subheadings would make the information easier to absorb.

The history section requires some attention, and it is important to put it in a chronological order. A number of references were not cited correctly and this needs to be corrected. It is important that you refer back to the tutorial on referencing as the citations are very important. Your glossary needs to be worked on and extended, it simply does not cover enough words within your project.

Where is the development section? This is one of the most important topics in the project in addition to function which need to cover signalling molecules and genes. The section on pressure however, is great, but the information needs to be put into tables or under more subheadings to make the information easier to read. At the moment information seems to be all over the place.

The current research section is great and should be expanded upon. The self drawn diagram about the somatosensory pathway is very informative and easy to understand. The references are great but some are included more than once and these need to be organised at the end of the page. Beside the limited diagrams, images, tables and organisation this page looks very promising.

taste

The information provided is both informative and well organised. The use of tables and figures make the text easy to follow and the diagrams make the information easier to understand. When it comes to images however, they seem to be somewhat irrelevant to the information they are associated with. Try to move them around and make sure they accompany relevant text.

The introduction does not give the reader the overview of the topic, but rather explores structures and function which makes it difficult to understand. Simplifying the introduction, and moving some of the more detailed information such as the information about the type 2 receptors to the relevant section would improve the page.

Other information that is difficult to understand is the text which involves certain genes and molecules without explaining their function or role. Explaining these aspects of the genes and molecules would make the information flow better. The section on current research is very informative and seems to be complete. However, I did note some errors with the citation of the image used, correcting the references is very important. Another thing which I noticed is that a number of the images do not have the copyright information, this needs to be included for every image. .

A number of the references were repeated numerous times which to me seemed unnecessary. Week 8 of development for example have the same reference after a number of sentences which in fact only requires a single reference at the end of the paragraph. However, a variety of sources will improve the accuracy of the information and is a great alternative than to derive all the information from a single source.

There is a great focus on the anatomy and physiology of taste, however, it is important to remember that the focus of this project is about development, and therefore including a timeline or a table which covers this information is very important. The page seems to be very organised and the inclusion of tables and diagrams along with the extensive glossary make this page stand out. Well done.

Abnormal vision

The differentiation between genetic and environmental abnormalities is an excellent idea and stood out immediately. This differentiation adds on to the organisation of the page and allows the information to be read with ease. However, the inclusion of tables and flow chart would go well in the page and make the information easier to follow. In addition to this, it would be great to see a few external links to make the page more engaging and guide audience to more more detailed information about certain abnormalities.

The information included is very extensive and highlight a great level of research. However, some of the information seems to be quite complex and difficult to understand. It is fine to cover difficult to concepts, but try to expand on it to allow for people to understand it or provide external/internal links which would provide more information and make the content easier to comprehend.

Having explained the function of genes in development and then explained any possible abnormalities that can arise in abnormal lens/corneal/retinal development made the information much easier to grasp. It allowed the information to flow and and the text seemed to follow a logical order. The inclusion of images in this section is great, whereas more images/diagrams is required for the rest of the page.

Covering the normal development is important and the chronological order used makes it easy to follow, however, keep in mind that there is a different project solely on normal development and therefore try not to expand to much about this topic. The referencing seems to be correct, and it is great to see a large range of sources have been used. One section that will require some work is the current research section as it does not seem like there is enough information. Apart from the issues raised, this page seems very promising.

Hearing

The introduction gives a good overview of the project and serves its purpose well. In addition, the technology section is another thing that stands out in this page along with the glossary and extensive referencing. These sections don't need to be worked on, but rather concentrate on expanding the page and adding a few more subheadings including headings of "current treatment" and "infection".

Information is very easy to follow due to the right choice of subheadings, tables and graphs. A few more tables and images with labels would make the information even easier to understand. Sometimes the amount of information becomes overwhelming, therefore try to break up the amount of texts by adding diagrams in between. Student hand drawn diagrams would be an excellent tool to employ as they can go well with the information provided.

The division of information between inner/middle/outer ear makes the structure easy to follow. This is a very good idea and an example as to how to break up the rest of the information which is all crammed together. The citation and referencing seems to be correct, however, there are a number of paragraphs without any references, this is something that needs to be looked into. However, the level referencing at the end is great.

Also, there does not seem to be enough links. A few external links will benefit the page and allow readers to interact a fraction more. Overall the page is very informative, however, altering the outlay and including a few diagrams, labeled images and external links would make the information easier to apprehend.


Lab 9

1.Identify and write a brief description of the findings of a recent research paper on development of one of the endocrine organs covered in today's practical.


<pubmed>23006330</pubmed>


Research have shown that heterozygous mutations in GATA6 have been detected in neonatal patients with diabetes who have not experienced a successful pancreatic organogenesis. In this study, GATA4 and GATA6 genes were inactivated within the pancreas in the presence of different conditions. Results indicated that a single activation of either GATA4 or GATA 6 had little effect on pancreas formation. However, when both genes were inactivated simultaneously, the mutant mice failed to undergo pancreas organogenesis, and no pancreata were formed. [1]


The mice did not survive long after birth and indicated high levels of hyperglycemia. Mutant mice which had morphological defects in Gata4/Gata6 had apparent pancreata during development and cell proliferation, however, due to mutation in Gata4/Gata6 genes, the epithelium of pancreata did not expand as Gata4/Gata6 genes are responsible for cell proliferation and differentiation. Multipotent pancreatic progenitors, in addition to PDX1+ cells were reduced in number during the double gene mutation and therefore affecting the development of pancreatic epithelium. [1]


The deletion of a single GATA6 allele on the GATA4 conditional knockout mice had a major effect of on pancreatic mass by severely reducing during development. However, a single allele of GATA conditional knockout mice made it possible for normal pancreatic development to occur. The findings indicate that the development of the pancreas depend on the GATA4/GATA6 factors and also indicate the different contributions of each GATA factor. [1]



2.Identify the embryonic layers and tissues that contribute to the developing teeth.

Embryonic layers contributing to developing teeth: Ectoderm, Mesoderm, and the neural crest.

The processes of odontogenesis involves the interactions of cranial neural crest derived ectomesenchymal cells and and the ectoderm of the first pharyngeal arch. These two embryonic tissues undergo inductive processes at week 6 of embryonic development and begin to produce teeth buds. [2]

The ectoderm located in the first pharyngeal arch is responsible for the formation of the enamel of the tooth whereas the majority of dental papilla are fromed by neural crest cells. The cells which form the blood vessels in the pulp of the tooth is a network of cells which are mesodermally derived. [3]

  1. 1.0 1.1 1.2 Cite error: Invalid <ref> tag; no text was provided for refs named PMID23006330
  2. <pubmed>19266065</pubmed>
  3. <pubmed>21425080</pubmed>