Osmosis Lab Report

Explain the effect that increasing the Na+ Cl- concentration has on osmotic pressure and why it has this effect. How well did the results compare with your prediction?

In this lab experiment, half our group observed and measured osmosis using dialysis tubes that were represented as the semipermeable membrane. It is permeable to water and other small molecules but is impermeable to larger molecules such as the sucrose solution used in each of the four beakers and tubing. The other half of our group observed the tonicity of sheep blood to determine whether the blood was isotonic, hypotonic, or hypertonic. The 85 g/dL of NaCl solution was the ideal isotonic number in relation to the sheep blood cells as well as a reference to the other observations of the solutions.

Purpose: The purpose of this lab is to familiarize you with osmosis and, specifically, what happens to cells when they are exposed to solutions of differing tonicities.

The Osmosis and Diffusion lab was conducted to provide us with information on how built up mucus affects those conflicted by the recessive genetic disease, Cystic Fibrosis., due to a mutation to the membrane regulating chloride (Cl-). This mutation prevents the Cl- from leaving the cell causing the amount of sodium (Na+) in epithelial cells, which results in extreme mucus on the lungs and airways causing this disease to be fatal if not treated but treatment does not equate to a long lifetime. During the lab we took the data from three parts: Diffusion, Osmosis in an Elodea Cell, and finally the Role of Osmosis in Cystic Fibrosis. During Part 1 we looked at diffusion across a semipermeable membrane for starch and glucose, which resulted in both having a negative solution when placed in a semipermeable membrane. Then we looked at osmosis in the Elodea Cell to watch for the occurrence of Plasmolysis, when a cell’s plasma membrane pulls away from the cell, and how a plant cell is affected by both hypertonic and hypotonic solutions. Finally, we observed the role of Osmosis in Cystic Fibrosis using dialysis bags to represent a normal cell and a Cystic Fibrosis cell with the normal containing 1% NaCl while the Cystic Fibrosis bag contained 10% NaCl. After we ran the experiment, we looked at the Percent Change in Mass and compared them after 30 minutes. We found that Cystic Fibrosis cells didn’t change mass as much as the normal cell ending with a change in mass over -1%. The

The lab for this paper was conducted for the topic of osmosis, the movement of water from high to low concentration. Five artificial cells were created, each being filled with different concentrated solutions of sucrose. These artificial cells were placed in hypertonic, hypotonic, or isotonic solutions for a period of 90 min. Over time, the rate of osmosis was measured by calculating the weight of each artificial cell on given intervals (every 10 minutes). The resulting weights were recorded and the data was graphed. We then could draw conclusions on the lab.

These two Case Studies come from a National Center on Case Studies. I think that a case study approach is very useful in applying knowledge and this is what makes you learn it better. They may be a little daunting when you read them but I will help you go through them. Please ask for help so this topic becomes more enjoyable for you.

The hypothesis states that if the solution is hypotonic the results will decrease, if the solution is hypertonic the results will increase and if the solution is isotonic the solution will vary and or remain constant. In order to test the predictions of the hypotonic, hypertonic, and isotonic hypothesis for the solution  made during the study,  four samples of sucrose were taken and placed into two different beakers each containing a different concentration. Then dialysis tubing A was placed into beaker 1 with B, C, and D placed into beaker 2 for 45 minutes and weighted at 15 minute intervals. My finding in the study was that each of the four samples changed from their initial weight and for the most part accurately proved the hypothesis.

There were several steps completed to prepare for the experiment. Three dialysis tubes were filled with approximately the same volume of distilled water and then were tied shut. The initial mass (in grams) of the tubes was taken using a triple beam scale. I then filled three 500 mL beakers with 400 mL of water each and dissolved different masses of solute (table sugar) in each beaker in order to make 5%, 10%, and 20% solutions. The beakers were labeled accordingly, and then 20 g, 40 g, and 80 g (respectively) of table sugar was weighed out using a digital scale and placed into the corresponding beakers. The sugar was stirred in using a stirring rod until all of the solute was completely dissolved.

Exercise 1: Cell Transport Mechanisms and Permeability: Activity 3: Simulating Osmotic Pressure Lab Report Pre-lab Quiz Results You scored 100% by answering 4 out of 4 questions correctly. 1. Which of the following is true of osmosis? You correctly answered: c. It is a type of diffusion. 2. Which of the following occurs when a hypertonic solution is added to cells? You correctly answered: d. The cells shrink. 3. The variable that affects osmotic pressure is You correctly answered: a. the concentration of nondiffusing solutes. 4. The net movement of water would be into the cell in a You correctly answered: b. hypotonic solution.

Cholera remains a drastically severe disease, killing hundreds of people each outbreak. When ingested, it attaches to the mucosal lining of the intestines and disrupts the normal flow of ions so that there is more sodium, chloride, and water in the intestinal lumen than normal and results in massive diarrhea. Cholera has made a global impact and been endemic in almost all parts of the world. Cholera control strongly emphasizes sanitation, clean drinking water, isolation, and careful food preparation. Two ways our body works against cholera as a self-limiting disease are sloughing cells and the secretory immunoglobulin (sIgA) antibody produced by mucus throughout our body. There are

Diarrhea being expelled from the body is not normal. This indicates that there is an issue within the gastrointestinal tract. Normally the small intestine absorbs most of the water in chyme. Approximately 95% of water is absorbed in the small intestine by osmosis (Marieb, 2014). The remaining water is usually absorbed in the large intestine, and some is even used to help soften the stool that is supposed to be pushed out. Peristalsis and segmentation in the small intestine helps mucosal cells absorb the water within the chyme. According to Marieb (2014), water moves freely in both directions of the intestinal mucosa, and active transport of solutes into the mucosal cells creates net osmosis because of the concentration gradient established. Therefore, water uptake is paired to solute uptake, and then affects the absorption of substances that

Group 1 received 107% for 0.0m, 109% for 0.25m, 112% for 0.5m, and 126% for 0.75m. Group 2 received 100% for 0.0m, 107% for 0.25m, 116% for 0.5m, and 117% for 0.75m. Group 3 received 100% for 0.0m, 106% for 0.25m, 114% for 0.5 m, and 117% for 0.75m. Group 4 received 100% for 0.0m, 106% for 0.25m, 113% for 0.5m, and 116% for 0.75m. Group 5 received 98% for 0.0m, 105% for 0.25m, 110% for 0.5m, and 115% for 0.75m. Group 6 received 104% for 0.0m, 108% for 0.25m, 111% for 0.5m, and 104% for 0.75m. The trend line that occurred for the rate of osmosis was an upward increase as the solute concentration increased.

The second phase of the disease involves the bacteria entering the immune tissue of the small intestine. This causes vomiting and diarrhea, often described as "pea soup." If left untreated, the bacteria can create a hole in the small intestine, causing intestinal matter to flood the abdominal area. If one is lucky enough to survive this illness without treatment, he or she can still be a carrier of the germs long after the symptoms have disappeared.

Produced by the bacteria, vibrio cholerae that creates a toxin that affects the absorption of water in the small intestine, Cholera is an infectious disease. The majority of the bacteria is wiped out by gastric acid when ingested, while the surviving bacteria settle in the small intestine and begin making the toxin that produces the symptoms of Cholera. The toxin created by the bacteria, Vibrio Cholerae, is a exotoxin. Vibrio Cholerae is a member of the Vibrionaceae family of curved gram-negative rods. They are found in coastal waters and estuaries, and tend to grow best in the company of salt. However, they can develope in lower salinity when it is warmer and contains sufficient organic materials. (Harris, LaRocque, Qadri, Ryan,

Cholera is an infectious bacterial disease of the small intestine. This bacterium has spread through the world covering about 50 countries that came about through 7 pandemics. This disease is a worldwide public health concern affecting 3-5 million people each year, killing 120,000. Before, it was thought that cholera spread through a sort of fog known as a miasma however now we know the whole mechanism for the cholera toxin. It was discovered that cholera is transmitted through fecal-oral transmission and is thus a waterborne bacterium. Although a very deadly and disturbing disease, even without medical education, this disease can be managed and usually even treated.