Cell Structure

After looking at many diagrams of cells I learned some specific parts of the cell.  If you follow the link you can see my Glog about cell structure! (click the word Glog) :)

Cystic Fibrosis :/

Many people don't even know what Cystic Fibrosis is, but at the same time, many people of all ages are being diagnosed every year.  Cystic fibrosis is a long-term disease that takes a toll on the lungs and digestive system of about 30,000 children and adults in the United States alone.  Overall there are around 70,000 diagnosed around the world.  In CF, a defective gene and its protein product cause the body to make unusually thick, sticky mucus that plugs up the lungs and can lead to fatal lung infections, and it also obstructs the pancreas and prohibits natural enzymes from assisting the body in breaking down and absorbing food.  In the 1950s, very few children lived to go to elementary school if they had cystic fibrosis.  Advances in research and medical treatments have further enhanced and extended life for children and adults that had CF.  Many people who are diagnosed with this deadly disease can now live into their 30s, 40s or older.  About 1,000 new cases of CF are diagnosed every year, and more than 70% of patients are diagnosed by the time they turn two.  However, more than 45% of the cystic fibrosis patients are 18 or older.  Unfortunately, the predicted median age of survival for a person suffering from cystic fibrosis is in the mid-30s.  People that have cystic fibrosis can have many different symptoms which may or may not include: very salty-tasting skin; persistent coughing, with phlegm; many lung infections; wheezing or shortness of breath; little growth/weight gain in spite of a healthy appetite; and other symptoms.
In the early 1980s, researchers found that the outer membranes of cells from people with the disease are poorly permeable to chloride ions, but biochemical analysis failed to identify the defective protein.  In 1985, they pinpointed the mutation to a small region located on chromosome 7.  The final breakthrough came in 1989, when the gene responsible for cystic fibrosis was finally isolated.  This is known as one of the most significant discoveries in the history of human genetics.  It led to improving the diagnosis of the disorder and improved the genetic counseling offered to affected families.  However, CF is a very complicated disease.  Not all of the the cystic fibrosis cases are caused by the same genetic defect.  About 800 different mutations have been identified in the CF gene, which affects the proper functioning of the CFTR, which is the Cystic Fibrosis transmembrane regulator protein.  The CFTR controls the flow of chloride ions from the cell.   The picture below shows the section through the cell membrane of an epithelial cell.  The CF transmembrane regulator channel is open in the image.

Cystic fibrosis generally happens in white people of northern European ancestry, occurring in about 1 out of 3,000 child births.  In the earlier days, people with this deadly disease died in their teens.  Improved screening and treatments now allow many people with cystic fibrosis to live into their 50s or older.

Tests that can be done in a lab are newborn screening tests, sweat tests, genetic testing, sputum tests, and organ function tests.  Imaging tests can be done by x-rays, computerized tomography, and magnetic resonance imaging.  There is also a lung function test which measures the size of your lungs, how much air you can breathe in and out, how fast you can inhale and exhale, and how well your lungs deliver oxygen to your blood.

Overall, Cystic Fibrosis is a very fatal and costly disease to patients and their families.  I learned that people with cystic fibrosis have a very tough life and it makes me realize that I take many things for granted that I never even thought about, such as breathing.  People suffering from CF have a hard time doing sports and even the small things like, walking.  Cystic Fibrosis attacks your lungs and makes you hack up gross mucus and keeps young kids from doing the things that I enjoyed while I was young.  After reading about this fatal disease, I am thankful for having good health and my heart goes out to those suffering from it.

Cell Membranes in a Fluid Mosaic Model :)

Lately in Biology we have been learning about the cell membrane and what exactly is in the cell membrane!  The cell membrane is a phospholipid bilayer.  The phospholipid bilayer has hydrophobic tails, which means they are attracted to water.  The phospholipid bilayer also has hydrophilic heads, making them scared of water.  Inside the phospholipid bilayer there are glycoprotein, proteins, cholesterol, glycolipids, carbohydrates, and many others.  In the cell membrane there is a protein channel.  After reading the word protein channel, using common knowledge, I just thought it was a type of system that carried along proteins throughout the membrane.  Well, in scientific terms, the protein channel are cells that create and install their own protein channels which are also called membrane structure, because cells need a way to move useful substances into themselves and pump the waste outside.  The proteins act like little machines moving around other molecules.  I also learned that carbohydrate chains serve as recognition makers.  We created cell membrane posters and labeled everything that was in a cell membrane.

Collagen :)

Many people may say what is collagen and why would we need to know anything about it, right?  Well it turns out collagen is EXTREMELY important to our bodies.  Collagen forms molecular cables that build up our tendons and have vast, resilient sheets that support our skin and internal organs.  Collagen is made up of three amino acids called glycine, proline, and hydroxyproline.  

Vitamin C plays a very important part in the formation of collagen.  Vitamin C helps in the addition of oxygen.  If a person doesn't get enough vitamin C in their diet the production of hydroxyproline and stops the making of new collagen.  This could cause scurvy, which is a severe disease.

Polypeptide chains are arranged by having every third amino acid as a glycine, and many of the remaining amino acids are proline or hydroxyproline.  

Osteogenesis Imperfecta is a bone disease and it is also referred to as the "brittle bone disease."  The main symptom of OI is bone fractures.  However, many other symptoms can occur such as: muscle weakness, hearing loss, fatigue, joint laxity, and scoliosis.  There are eight types of Osteogenesis Imperfecta.  Type I OI is the least severe and most common form of the disorder.  OI Type I is the differs from the other types of OI because the collagen structure remains normal.  OI Type II is the most severe form.  

The role of collagen in bones is very important because your collagen levels predict the strength of your bones.  Collagen problems often lead to bone problems because if you have an insufficient level of collagen, your bones are going to be weak and have "brittle bones", which means they break and fracture easily.

Overall, I learned that collagen is very important to know about and it is crucial to our bodies.  If we don't have sufficient levels of collagen we will have weak bones!!! :)

Untangling the Twisted Proteins that turn Brains into Sponge-Research Article

Just recently, there was a study about what causes mad cow disease and Creutzfeldt-Jakob disease which are fatal brain disorders.  These diseases are not caused by viruses or bacterium.  Creutzfeldt-Jakob disease and mad cow disease are caused by an abnormal formation of a protein called a prion.  Scientists and other studies are beginning to reveal that the prions help natural functions perform before they turn to the "dark side."  Jiyan Ma, a molecular biochemist at OSU, and colleagues transformed a normal protein made by E. coli bacteria into a prion that had the properties of the infectious version.  It starts out by forming clumps, declines being cut by enzymes, and changes other healthy proteins into the aberrant form.  Jiyan Ma and his colleagues injected the prion into the brains of mice, which caused their brains to become spongy and full of holes, initiating telltale signs of prion disease.  Their next step is to take a closer look at the system they used to make infectious prions to identify the molecular mechanisms behind the change.

In another experiment, researches in the U.S. and Austria used a prion protein also made by E. coli to contaminate hamsters with a transmissible brain disease.  The diseases worsened very gradually, similar to how it progresses in humans, referring that hamsters could provide a useful animal model system.

While most research is about the disease-causing prion protein, Adriano Aguzzi of University Hospital of Zurich is looking at the healthy forms of those proteins in humans.  He found that mice who laked those proteins showed a failure of the protective myelin sheath on their nerves.  The main task now is to find out why this protein goes bad at times.

http://discovermagazine.com/2010/jun/04-untangling-prions-twisted-proteins-brains-into-sponge

Carbohydrates :)

In boring terms, a carbohydrate is an organic compound Cm(H20)n, made of carbon, hydrogen, and oxygen. In easier and more understanding terms, carbohydrates are what gives our bodies energy.  In our lab we tested many different things such as honey, all the way to lactose powder.  I learned that when a disaccharide is mixed with Benedict's solution it does not change in color, when a monosaccharide is combined with Benedict's solution it turns an orange color, and when a polysaccharide is mixed with Benedict's solution, the ending result is a dark, thick substance.  Attached is a concept map of other things I have learned throughout the lesson.

Reflection on Stomach Acids

Lately in Biology we have been experimenting with stomach acids and what works to calm an upset stomach.  My group and I tested different types of antacids by placing two tablets into vinegar.  An antacid is any type of base or basic substance that neutralizes stomach acidity.  I learned that an acid is any substance that has a pH of six or lower.  Acids become less acidic when mixed in with a substance that is a base.  An acid increases the concentration of hydrogen ions, but bases lower the concentration of hydrogen ions, because they accept them.  A base is a substance which has a pH between eight and fourteen.  A base becomes less basic when mixed with acidic substances.  Pure water, on the other hand, is neutral because it maintains a pH of 7.  The pH is calculated in logarithmic units of ten in the acidity or baseness of a substance.  For example, orange juice is ten times more acidic than tomato juice, because orange juice has a pH of three while tomato juice has a pH of four.  

Antacids help calm the acids that are in your abdomen.  I found out that about the only difference in generic brands and name brands of antacids is the price.  So, next time you go to the store to buy antacids, don't fall for the expensive brand, because in all actuality they work the same.