Hayley+J.


 * Post #3- Alzheimer 's Disease **

Alzheimer's is a that causes problems with, thinking and behaviour. It is one of the most common for more than 50 to 80% of cases. Symptoms usually worsen over time, in most cases becoming severe enough to interfere with every day tasks. Alzheimer's disease is very common among the elderly but there arecases of the effecting people as young as forty.
 * What is Alzheimer's ? **

A big part of this disease starts with amyloid nd neurofibrillary tangles. Amyloid plaques are made up of and material around the in the brain. The tangles are twisted fibers that build inside of the nerve cells. Scientist Dr. was the first to them after looking into the of a woman in 1906.

This is Dr. Alois Alzheimer, the man who dicovered the plaques and tangles.

Progression of the diease causes the nerve cells in the brain to shrink and eventually die. These cells can be very important in brain activity, being a huge contributor to the cells in neurotransmitters.

This diagram shows the progression of Alzheimer's and how the brain changes througout.

A video on the science behind Alzheimers. media type="custom" key="24842266"

Symptoms and signs
- Having difficulty performing routine tasks that have a bit of difficulty - in familiar places - Having a hard time everyday - Misplacing thing - Change in personality and As the desease, the become worse: - Basic tasks become more difficult, such as changing and cooking - Losing memories of the past and losing ones self - Writing and become difficult - Socializing lessens - Less ability to sense - Mispronouncing words, jumbling sentences, using the wrong words - Violent behaviour

And lastly with severe Alzheimer's: - Do not understand language - Do not recognize family or friends - Can not complete everyday tasks

Further : [] Super neat digital tour of the brain [] this site talks about how clinical trials are made for Alzheimer's [] this site states normal aging vs. Alzheimer's [] this is what family members need to watch for and how they can detect the disorder [] Doctor Oz gives some tips on preventing Alzheimer's

Sources: [] [] [] []


 * Post #2- Continental Drift **

=
, a German was the to publish the idea of what he called continental shift. In the early 20th century he published a that explained his theory of giant land masses moving across the Earth. He noticed that the coast of and the coast of seemed to look like they could have fit together in a puzzle manner. He continued his research by noticing that the two continents had both biological and physical similarities which clarified the revolutionary idea. Wegener believed that all the continents had once been joined together to form one huge mass of land know as Pangaea. Pangaea is Greek for "all lands" and is thought to have existed 240 million years ago. The super continent started breaking up around 200 million years ago and over millions of years continued to move to form the continents we know today.=====

= =

I found this mildly entertaining and I think it does a great job at explaining Alfred Wegener's theory in an interesting way. media type="custom" key="24507324" align="center"

In spite of the criticisms from several different colleagues, Wegener was able to keep Continental Drift part of the discussion until his. Although the jig saw puzzle theory was impressive he knew that he would need to strengthen his so he found, geography, biology and paleontology facts to help his theory. He presented examples where fossils of were found over the length of multiple continents. He knew it was not possible for plants or land animals to swim across an ocean so that meant that at some point every species would have shared a single super continent.

The above shows the of fossils on the different continents.

As I mentioned before, Pangaea is known as the "". It is thought to have existed over 300 million and began to break up about 200 million years ago. The fragmentations of the super continent subsequently gave us the continents we have today. Although we will not see it in our life time, it is possible for a new super continent to form. The Atlantic ocean is getting wider as a result of the plate movement and the Pacific ocean seems to be closing.
 * P **** angaea **

This image shows the different stages of the Pangaea throughout the years and how our continents came to be the way they are today.

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=
The continental drift theory become much more popular after the theory of tectonic plates became better known. The theory of plate tectonics state that Earth's outermost layer, the lithosphere, is broken into 7 large, rigid pieces called plates: the African, North American, South American, Eurasian, Australian, Antarctic, and Pacific plates. These plates are all moving at different speeds as well as in different directions. The speed can vary from 2cm to 10cm per year. Earthquakes, mountain- building, ocean trenches and volcano activity happen along the boundaries of the plates. There are three different types of tectonic plates; divergent, convergent and transform. =====

This picture shows the three different types of tectonic plates and the different directions that they are moved.

=Further Reading:= [] continental drift animation [] everything you need to know about plate tectonics [] article about Alfred Wegener [] step by step explanation of continental drift =Sources:= [] [] [] [] []

= = = Wiki Post #1- Conjoined Twins = = October 11, 2013 =

We all know at least one pair of identical or fraternal twins but with only one in every 200 000 births it is a lot more rare to see a pair of conjoined twins. This abnormality is commonly referred to as Siamese twins, which are essentially identical twins that are joined in utero. Approximately half are still born and some that are born alive face life-threatening complications that end in death. Conjoined twins have a 25% overall survival rate and up to 70% of the living twins are female.

This is a picture of Chang and Eng Bunker, considerably the most famous pair of conjoined twins, in 1836. The twins were referred to as the Siamese twins and because of their fame the term 'Siamese twins' became a synonym for conjoined twins. The term is now considered derogatory to some people.

Scientists believe conjoined twins form because of a delay in the fertilized egg's division. In normal identical twins the egg splits at four to eight days after fertilization but in conjoined twins the split happens sometime after day 13. Instead of forming two separate embryos, the twins stay partially attached as they develop inside the womb. In most cases, conjoined twins do not survive more than a few days past birth because of malformed organs and other birth abnormalities.
 * The Science Behind It **

This diagram shows the formation of the conjoined twins in the embryo There are over a dozen different types of conjoined twins but doctors have chosen to categorize them in 9 major groups: __Thoracopagus__: Ventral or front union at the chest, often with a shared heart. Separation has been attempted but twins do not survive. __Pyopagus__: Dorsal or rear union at the pelvis. This is rare but can be easily separated. __Ischiopagu__s: Ventral or frontal union at the pelvis, often connected by bladder, kidneys, intestines and genitals. This is a more difficult separation and will result with problem in excretion and sexual functions. __Craniopagu__s: Dorsal or rear union at the head. Separation is possible although brain damage is common. __Parapagus__: Lateral or side union, this is an easy separation but the result will e artificial limbs. __Omphalopagu__s: Ventra or Frontal union at the abdomen, this type of twin has the highest survival rate. __Cephalopagus__: Ventral or frontal union at the head and chest. These twins do not survive. __Rachipagus__: Dorsal or rear union at the spine, very rare. __Parasitic__: Twin has an additional limb, thought to be caused by the death of one of the twins in utero.
 * Types of Conjoined Twins **

This photo shows 8 of the 9 major groups of conjoined twins. It does not include parasitic.

This video shows how truly fascinating conjoined twins are and how it is possible to live a normal life as a conjoined twin and as separated twins.

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Its not only possible for humans to be conjoined twins but it has also been found in animals! The survival rate for conjoined animals is much lower than humans and they are also a lot more rare. Their have been reported cases of conjoined buffalo, dogs, fish, cats, insects, turtles and more!
 * Conjoined Animals **



[|http://www.theatlantic.com/health/archive/2012/10/the-sex-lives-of-conjoined-twins/264095/] Don't deny it, you were wondering about their sex lives so here it is... [] Awesome pictures of conjoined twins [] articles on living conjoined twins [] The history of conjoined twins
 * If you are interested in this topic and want to find more information check out these websites! **

**Sources:** [] [] [] [] []