Understanding Cystic Fibrosis

Cystic fibrosis is a genetic disease that primarily affects the respiratory and digestive systems. The life-threatening disease is caused when a defective gene and its protein product cause the body to produce  unusually thick and sticky mucus that can clog the lungs and obstruct the pancreas.

Symptoms of cystic fibrosis (CF) can include very salty-tasting skin, persistent coughing, frequent lung infection, wheezing, shortness of breath, poor growth, gradual weight gain (despite a healthy diet), and frequently greasy, bulky, or difficult stools. There is an estimated 30,000 children and adults diagnosed with CF in the US, 70,000 world wide. Testing for cystic fibrosis can be handled in several ways, including sweat tests, newborn screening, and carrier testing. Positive results on these tests could lead to a diagnosis for CF.

Cystic fibrosis is passed down genetically when a child inherits one copy of the defective gene from each parent. CF is a recessive gene, which means that a person must have both copies of the mutated gene in order to be affected by cystic fibrosis.

https://patientcontent.blob.core.windows.net/media/Default/StudentArticle/student/cystic-fibrosis/cystic-fibrosis-inheritance.jpg

In a non-defective gene, the protein acts as a gateway, allowing ions to bring water to the surface of the airway. This keeps the mucus moist. In CF patients, the vital chloride channel is blocked, preventing the movement of chloride ions into the mucus.

http://dm5migu4zj3pb.cloudfront.net/manuscripts/37000/37778/medium/JCI0837778.f1.jpg

This then halts the movement of water, causing the mucus to dry out. The mucus builds and begins to clog the lungs and obstruct the pancreas.

http://270c81.medialib.glogster.com/media/fa/faa1a7acc077a88fe83a10c17ad142bef9ed47b4aec1a358651840b4b6d209bc/cystic-fibrosis-mucus-diagram.jpg

http://www.nhlbi.nih.gov/news/images/cysticfibrosis01.jpg

While there is no known cure for cystic fibrosis, there are several options for treatments that will reduce the symptoms and their effects. There are several medication options for CF treatment, including antibiotics, mucus-thinning drugs, bronchodilators, and oral pancreatic enzymes. Other treatment options include chest physical therapy, pulmonary rehabilitation, and surgical or other procedures.

When a child or loved one is diagnosed with CF, it is very important to care for them and offer full support. There are several ways to bring aid to a CF patient, including encouraging better nutrition, heightened fluid intake, updated immunizations, exercise, and hand washing. It is also vital to illuminate smoke from the patient's surroundings, as it will only irritate the respiratory tract and increase the issue. 

Osmosis Lab Report

Objective:
A lab partner and I created this experiment in an attempt to model osmosis, the traveling of molecules of a solvent across a semipermeable membrane in an attempt to equalize the concentrations on both sides of the membrane.

Procedure:
To model the process of osmosis, we set up several beakers that contained water, dialysis tubing, and a salt solution. Each was modeled differently, depending on where the salt was located. Each beaker is detailed below:


Beaker A: Dialysis tubing filled with water sealed inside, tinted with food coloring, surrounded by a salt solution.
Beaker B: Dialysis tubing filled with a salt solution sealed inside, surrounded by water, tinted with food coloring.
Beaker C: Dialysis tubing filled with solid salt sealed inside, surrounded by water.
Beaker D: Dialysis tubing filled with carbon dioxide sealed inside, surrounded by water.


Before placing the dialysis tubing in the beakers, we measured the mass of each tube after they had been filled with their solutions/contents. 24 hours later, we measured again so that we could track the movement of the water.

Claims:
It can be concluded that the water diffused to areas of higher concentrations, such as the ones that contained high amounts of salt.

Evidence:

The graph organizes the results from the experiment, proving the water traveled from areas of lower concentration to areas of higher concentration. Based on the contents of the beaker and dialysis tubing, the ending mass of the tubing varied in proportion to the movement of the water.

Research:
In a similar experiment conducted using potatoes instead of dialysis tubing, the same general results were found. The same general results were also found when using eggs instead of potatoes or dialysis tubing. When experimental results were explored during a class session, it could be concluded that all experiments yielded similar results.

Reflection:
Reflecting on this experiment, I am very satisfied with the results. Throughout the process, I was able to understand the reasoning behind the results and predict what would happen. I believe the experiment could be improved by trying to reverse the experiment. Would placing the dialysis tubing (after the first 24 hour testing period) into new beakers with different concentrations reverse the original direction of the water? It would be interesting to try to control the flow of the water through several different tests.

Diffusion Lab Report

Questions:
The goal of this experiment was to model how a cell membrane functions. This includes what types of substances are able to pass through the membrane, and how the membrane passes them through to the inside of the cell.

Procedure:
For this experiment, dialysis tubing was used to model a cell membrane. The tubing was filled with a glucose and starch solution, then tied at each end. The mixture was used to model the inside of the cell. The "cell" was then placed in a beaker that was filled with a iodine/water mixture. After 24 hours,  the solutions in the beaker and dialysis tubing were tested for the presence of glucose and starch. The presence of glucose will be tested using indicator strips; the presence of starch will be tested based off of the chemical reaction indicators between the starch and iodine. Starch forms a blueish black complex with iodine whereas glucose does not react.

Claims:
Based off of the results from the procedure, it can be determined that the starch remained inside the dialysis tubing, and the iodine diffused into the dialysis tubing. While some glucose diffused into the beaker, the inside the tubing also tested positive for containing traces of glucose. The water diffused into the tubing until it could not contain any more. The results of the experiment proved that molecules move from regions of higher concentration to lower concentration during diffusion. 

Evidence:
The following table displays the results drawn from the experiment that support the previous claim.

"+" represents a positive test, "-" represents a negative test

Solution Color

                                  Initial Contents                  Initial            Final           Initial        Final

     Bag          15% glucose, 1% starch         milky white         black             +             +  

    Beaker           H2O+IKI                         yellow/brown       yellowish       -              +

It can be concluded from the evidence in the chart that the glucose diffused into the beaker and the iodine diffused into the dialysis tube.

Research:

When compared to results drawn from similar experiments, online information resources, and notes taken during class lectures, it can be confirmed that molecules move from regions of higher concentration during diffusion.

Reflection:

Reflecting on this experiment, the ideas and data constantly supported the results. I believe it could be improved by tracking the motion of the water to observe if it diffused.

Pictures:

Glucose strip before the experiment

Glucose strip after experiment

Dialysis tubing with starch and glucose before the experiment

Dialysis tubing with starch and iodine after the experiment

Fluid Mosaic Membrane Model Quiz Questions

1) What part of the phospholipid is on the outer face?
2) What is the difference between peripheral proteins and integral intristic proteins?
3) What is the purpose of the glycoproteins?
4) The part of the phospholipid that is hydrophobic is known as the what of the phospholipid?
5) What is the purpose of cholesterol in a fluid mosaic membrane?

1) The hydrophilic.
2) Intristic proteins are bound within the plasma membrane of the cell. Peripheral proteins do not     penetrate the membrane.
3) Glycoproteins help with hormone function by binding them to the protein receptor molecule.
4) The tail.
5)  Cholesterol strengthens the membrane and helps it remain fluid.

Fluid Mosaic Membrane Model

This post focuses on the components to a fluid mosaic membrane. To demonstrate this, a group of people, including myself, created a poster that detailed these components.

What are biological membranes? Biological membranes are sheet-like structures that are composed of lipids and proteins. The lipids and proteins move with a fluidity throughout the membrane. A fluid mosaic model captures both the fluidity of the membrane and the mosaic arrangement of the proteins and lipids within the membrane structure. The poster pictured above has the components of the membrane labeled. 

Collagen Web Quest

The goal of this post is to accurately portray the concepts of collagen, one of the most important structural proteins found in your body.

Part 1.

1. Describe the primary structure of collagen. What are the major amino acid components in collagen?

Collagen is a protein made up of amino-acids: glycine, proline, hydroxyproline, and arginine. The primary structure of a protein is its linear sequence of amino acids and the location of any disulfide (-S-S-) bridges.

2. What role does vitamin C play in collagen formation? What happens when a person does not get enough vitamin C in his or her diet?

Vitamin C adds hydrogen and oxygen to amino acids, so that they may do their part in collagen production. If a person doesn’t receive the proper amount of vitamin C in their diet, collagen production will slow.

3. Describe the quaternary structure of collagen.

Three polypeptide chains are wound together in a braid-like fashion, linked when a glycine fits into the helix. The other “gaps” are filled with proline and hydroxyproline, forming a triple helix.

Part 2.

1. What is the main symptom of osteogenesis imperfecta?  What are some other symptoms that people with OI may have?

The most common symptom of OI is the fracturing of bone easily. In addition to fractures, symptoms also include muscle weakness, hearing loss, brittle teeth, and short stature.

2. Type I osteogenesis imperfecta causes fewer problems than the other forms. How does the collagen structure in Type I OI differ from that of the other types?            The collagen structure found in type 1 osteogenesis imperfecta is normal, while the structure of collagen in other forms of OI is improperly formed.

3. Describe the role of collagen in bones. Why do collagen problems lead to bone problems?

Collagen help make the structure of bones, forming the “rods” that add strength. People with OI have weaker bones from improper formation or lack of collagen present in their bodies.

Sources:

http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/P/PrimaryStructure.html

http://www.biotopics.co.uk/JmolApplet/collagen.html

http://www.oif.org/site/PageServer

http://www.oif.org/site/DocServer/Bone_Structure.pdf?docID=7186

Carbohydrate Identification

Questions:

The goal of this activity was to determine how to differentiate the types of saccharides based on how they reacted in iodine and Benedict's solutions.

Procedure:

Mono, Di, and Poly saccharides were tested for reactions in iodine and Benidict's solutions. Several sugar samples were then tested for reactions in the same solutions. The type of saccharide was determined based on the samples' reactions when mixed with the two solutions compared to the reactions of the pure saccharides when mixed with the solutions. If there was a reaction between the saccharide and the iodine, the reaction occurred immediately. The Benedict's solution needed to be heated with the saccharide before a reaction could occur.

Claims:

Based off of the evidence produced during the procedure, it can be determined that if a saccharide reacts to the Benidict's solution and not the iodine solution, it can be positively identified as a monosaccharide. If a saccharide reacts to the iodine solution and not the Benedict's solution, it can be positively identified as a polysaccharide. If a saccharide does not react to either solution, it can be positively identified as a disaccharide. Each type of saccharide could be identified based off of their reactions in the two solutions.

Evidence:

The claims of this experiment can be proven with the evidence gained throughout the procedure. The tables below display the evidence gathered from the experiment. (+) indicates a reaction while (-) indicates no visible change.

      Sample        Benedict's            Iodine
Monosaccharide                     +                                    -
      Disaccharide                           -                                     -    
 Polysaccaride                          -                                    +

           Sample        Benedict's            Iodine
      Powerade                          +                                    -    
Corn Starch                        -                                    +
Niagara Spray Starch         -                                    +
Kix Cereal                          -                                    +
Galactose                           +                                    -

   

Research:

 When compared to other groups' findings, nutrition facts, information gathered in class, and web sources, it is clear that similar conclusions were, or could be drawn from this experiment.

Reflection:

Through this experiment, ideas have remained consistent throughout the discovery of new findings. Though new questions were rasied throughout the scientific process, each could be traced back to the original hypothesis that the saccharides could be successfully differentiated based on the chemical reactions visualized when mixed with each solution. Improvement in the experiment could include the testing of known poly, di, and mono saccharides to prove their saccharide content.

Lab Analysis Questions:

Further explanations on this lab topic can be found at this address:

https://docs.google.com/document/d/17lgAoM3J1tLVKSvwo0o1hbDMoRaB42a8uaEJlMqZit4/edit

Pictures from the Experiment:

These pictures were taken directly from the experiment without other sources.