Alyson+M.

=Post 1 March 2013-Genetics=

What are genetics?
Genetics are the study of heredity and heredity is a biological process where a parent passes certain genes that are passed onto their children. Every child inherits genes from both of their biological parents and these genes in turn express the child's specific traits. Some of these traits may be physical for example hair and eye color and skin color etc. On the other hand some genes may also carry the risk of certain diseases and disorders that may pass on from parents to their offspring.

= Cystic Fibrosis =

= What is Cystic Fibrosis? =

Cystic Fibrosis (CF) or Mucoviscidosis is a dangerous genetic disorder that causes severe lung damage and affects digestion. CF affects the movement of salt in and out of cells that produce mucus, sweat, saliva, and digestive juices. The defective gene causes the secretions to become thick and sticky instead of thin and slippery. The secretions then begin to clog up the lungs, ducts, tubes, and passageways. The mucus clogs up the lungs, causing respiratory failure and breeding ground for bacteria to grow. This leads to repeated lung infections that can cause serious damage to the lungs. The secretions can also block areas in the pancreas so the digestive fluids can not travel to the small intestine, where they are needed to break down food. The intestines cannot absorb fats and proteins fully. The secretions also prevent the body from absorbing key vitamins.

=How Cystic Fibrosis Affects The Body= media type="youtube" key="kYzlx_TOgFg" height="315" width="560"

What Causes Cystic Fibrosis?
A defect in the CFTR gene causes cystic fibrosis. This gene makes a protein that controls the movement of salt and water in and out of your body's cells. In people who have CF, the gene makes a protein that doesn't work well. Research suggests that the CFTR protein also affects the body in other ways. This may help explain other symptoms and complications of CF. More than a thousand known defects can affect the CFTR gene. The type of defect you or your child has may affect the severity of CF. Other genes also may play a role in the severity of the disease.

**How is Cystic Fibrosis Inherited?** Every person inherits two CFTR genes—one from each parent. Children who inherit a faulty CFTR gene from each parent will have CF. Children who inherit one faulty CFTR gene and one normal CFTR gene are "CF carriers." CF carriers usually have no symptoms of CF and live normal lives. However, they can pass the faulty CFTR gene to their children.

Symptoms of Children and Adults:

 * Coughing or wheezing that brings up phlegm (flem)
 * Salty taste on the skin from the increased salt content in sweat
 * Greasy stools
 * Intestinal blockage, called meconium ileus, in a newborn
 * Delayed growth, in spite of a big appetite
 * Infertility
 * Dehydration
 * Frequent lung infections such as bronchitis and pneumonia

Cystic Fibrosis Can Also Be Followed By:

 * - Sinusitis- When the sinuses, which produce mucus and keep the lining of the nose moist, become swollen.
 * - Bronchiectasis- A lung disease where the bronchial tubes flabby and form pockets from the excess mucus. This becomes a place for bacteria to grow. This leads to lung infections and can lead to serious illnesses.
 * - Pneumothorax- collapsed lung
 * - Clubbing or enlargement of the fingertips or toes.
 * - Nasal Polyps- growths in the nose
 * - Pancreatitis- inflammation in the pancreas
 * - Rectal Prolapse
 * - Intestinal blockage
 * - Liver disease

**Normal Lung Compared To Collapsed Lung**

More Information On Cystic Fibrosis: About Cystic Fibrosis and Canada: [] Causes, Symptoms and Treatments: [] What is Cystic Fibrosis and living with it: [] The history behind Cystic Fibrosis: []

References: [] [] [] http://runkle-science.wikispaces.com/Cystic+Fibrosis

= Post 2-Genetics #2 =

About Down Syndrome
Down Syndrome, also called Trisomy 21, is a condition in which extra genetic material causes delays in the way a child develops mentally and physically. It is caused by an extra chromosome 21. It affects about 1 in every 800 babies born in the United States.

The physical features and medical problems associated with Down Syndrome can vary widely from child to child. Some kids may need a lot of medical attention, while others live healthy lives. Although Down Syndrome can not be prevented, it can be detected during pregnancy. The health problems that may go along with DS may be treated and many resources are avaliable to help kids and their families dealing with the condition.

Down Syndrome child with his family

What Causes Down Syndrome?
At the time of conception a baby inherits genetic information from its parents in the form of 46 chromosomes: 23 from the mother and 23 from the father. In most cases of Down Syndrome, a child gets an extra chromosome 21 for a total of 47 chromosomes instead of 46. It's this extra genetic material that causes the developmental delays and physical features associated with Down Syndrome.

Extra Chromosome 21 that causes Down Syndrome

Who is at the Highest Risk of Conceiving a Child With Down Syndrome?
No one knows for sure why Down Syndrome occurs and sadly, there;s no way of preventing it. Scientists though, do know that women aged 35 and older have a significantly higher risk of having a child with this condition. At age 30, a woman has about a 1 in 1000 chance of conceiving a child with Down Syndrome. These odds increase to about 1 in 400 by age 35. By age 40, it increses again to 1 in 100.

Effects on Children With Down Syndrome
Kids with Down Syndrome often share the same physical features such as a flat facial profile, and upward slant to their eyes, small ears, and a protruding tongue. Low muscle tone called "Hypotonia" is also a characteristic of children with Down Syndrome and babies in particular may be most affected by this. Though most of the time, this does improve over time, most children with Down Syndrome typically reach developmental milestones like sitting up, crawling and walking, later than other kids.

At birth, a child with Down Syndrome is usually of average size, but they tend to gown at a slower rate and remain smaller than others. Low muscle tone may contribute to sucking and feeding problems, as well as constipation and other digestive problems. Toddlers and older kids may have delays in speech and self-care skills like feeding, dressing and toilet teaching. It also affects their ability to learn like other students, but this doesn't mean they can't learn at all. They do this at a different pace and in different ways, but should never be compared to children without this disability. There is no way to tell at birth what a child with Down Syndrome will be capable of as they grow up.

Woman With Down Syndrome

Learning About Down Syndrome
media type="youtube" key="1yzMKxt53ho" width="420" height="315"

Getting Help for Your Child With Down Syndrome
Physical, occupational, speech therapists and early-childhood educators can work with your child to encourage and accelerate development. Many states provide free early-intervention services to kids withdisabilities from birth to age 3. Checking with a doctor or a social worker to learn what resources are available in your area would be a big help as well.

Once your child is 3 years old, he or she is guaaranteed educational services under the Individuals with Disabilities Education Act (IDEA). Under IDEA, local school districts must provide a free appropriate education in the least restrictive environment and an Individualized Education Plan (IEP) for each child. Choosing where to send your child may also be a tough decision depending on what level of help you and your child are seeking. Some children with Down Syndrome don't need help as advanced as other children with Down Syndrome do.

Possible Effects of Down Syndrome


More Information on Down Syndrome: Facts:[] Learning About Down Syndrome:[|http://kidshealth.org/parent/medical/genetic/down_syndrome.html#] []

References: [] [] = = =Post 3- Human Evolution=

What is Human Evolution?
Human evolution is the long process of change by which people originated from apelike ancestors. Scientific evidence shows that the physical and behavioral traits shared by all people originated from apelike ancestors and evolved over a period of approximately six million years.

One of the earliest defining human traits, "Bipedalism" the ability to walk on two legs, evolved over 4 million years ago. Other important human characteristics such as large and complex brain, and the ability to make and use tools, and the capacity for language, developed more recently. Many advanced traits including complex symbolic expression, art, and elaborate cultural diversity, emerged mainly during the past 100,000 years.



Evidence of Evolution
Scientists have discovered a wealth of evidence concerning human evolution, and its shown in a few different ways. Thousands of human fossils allow researchers and students to study the changes that occurred in the brain and body size, locomotion, diet, and other aspects involving the way humans lived their lives 6 million years ago. Traces of human behavior like finding millions of stone tools, figurines, paintings, and footprints shown in the prehistoric record tell us about where and how early humans lived and when certain technological items were invented. The study of human genetics also show how closely related and connected we are to the other primates.

Evolved fossils

Tool Making
Early humans were known to use stone and wood as hammers to crack nuts and as crude ineffective weapons for hunting small animals. However, they rarely shaped their tools in a systematic way to increase efficiency. The most sophisticated tools that were used are small, slender tree branches from which they strip off the leaves. These twigs are then used as probes for some of their favorite foods such as termites and ants. The first unquestionable stone tools were evidently made and used by early humans in East Africa about 2.5 million years ago.

Tools used by early humans

=Early Human Evolution= media type="youtube" key="IRnr0NQppxw" width="420" height="315"

References: [] [] []

More information on human evolution: [] [] []