The rate of diffusion is said to be dependent upon the various factors: size of molecules that have to diffuse, concentration gradient, the distance across which diffusion occurs, number of pores/openings, surface area and concentration. This rate of diffusion is measured by considering the time taken for changes to physical changes to occur. This experiment consists of using agar mixed with an indicator that changes color when places in a basic solution. It will measure the amount of diffusion that occurs in the agar blocks to determine the effect of cell size on the cells ability to obtain substances by diffusion. Purpose:Determine how surface area and volume relate to one another and how the rate of diffusion varies with the ratio of surface area to volume. In the experiment, we will use the base/acid indicator Phenolphthalein in three different sized agar cubes dipped in a sodium hydroxide solution. This will make it possible to measure the depth to which the color has penetrated and will demonstrate the relationship between diffusion and volume. Materials: -agar -scalpel -spoon -two large beakers -ruler -timer -potassium manganate (K2MnO4 ) -hydrogen chloride (HCl methods: -make two trays of Agar Gelatin.
Lab report on osmosis and diffusion - custom Papers
This is unlike the rest that are the diffusion of molecules. In ponytails a bit of enfolding plasma membrane surrounds a very small volume of extracurricular fluid containing dissolved molecules. These "cell drinking cells" are also called fluid-phase endometriosis. The fuse with endmost occurs when the droplet enters the cell. Ponytails is a routine activity of most cells, affording them a nonconsecutive way of sampling the extracurricular fluid, unlike phagocytes. Phagocytes is engulfing of foreign solids by cells. Experiments were conducted in order to gain a better understanding of a cell's selectively permeable membrane and the passive recesses of simple and facilitated diffusion. Let Us do your Essay for you - for less than 14 per page you can forget about that worry! Diffusion in agar cubes, introduction: All cells are dependent on a processes called diffusion, objektif which is the movement of a substance from an area of higher concentration to an area of lower concentration. Cells need to obtain certain essential substances, like oxygen, for their survival.
Molecules use their kinetic energy as the motivating force in diffusion. Facilitated diffusion occurs when molecules are too large to pass through summary a membrane or are unable to be dissolved into the lipid bi-liar. The process or act is when the carrier protein molecule located in the membrane combine with solute and transports them down the concentration gradient. Established gradients are due to the pressure of molecules on each side of the membrane's wall. Also the membrane's pore size and amount of pores depends on the amount of molecules and fluids in the filtrate. Another type of passive rainspout that is not a selective process is called filtration. Furthermore, the process filtration is when the water and solutes pass through a membrane (such as a dialysis membrane) from an area of higher hydrostatic (fluid) pressure into an area of lower hydrostatic pressure; which means that water and solutes would pass through a selectively. Finally the last type of passive transport is called osmosis; which is the diffusion of solvents, such as water, through a selectively permeable membrane.
There are two methods of transport which can occur through the plasma membrane. To be discussed first, the method of transportation is called active transport which uses tap (glucose) or energy to move substances through the membrane. Secondly, the method oaf passive transport does not require the use about of tap (glucose) or energy. During passive transport (or gradient molecules are moved through the membrane of the cell by the imbalance of molecules and or pressure between the inside and outside of the cell. Simple diffusion, facilitated diffusion, osmosis, and filtration are all types garden of passive transports. In a living human body the cells use diffusion as the important transport process through its selectively permeable membrane. Diffusion is defined as the movement of particles from an area of higher concentration to an area of lower concentration, which results because of the random movement of particles. Osmosis is the diffusion of water into and out of a selectively permeable membrane. Because of the selectively permeable membrane, nothing but water and other very small particles can be diffused wrought osmosis.
We will write a custom essay sample specifically for you for only.90/page order now, the step by step process was used by the software so that we could see the different kinds of reactions. According to the data found, we found that with high molecular weight compounds are too large to penetrate the molecular weight cut off pores and no simple diffusion can occur. So it seemed like the easiest way for a solute to pass through a semiprivate membrane was, if it either was small enough to pass or had some sort of carrier protein that helped it along. We expected to see continuous results that do not have much difference in the five experiments that are to be reformed. Experiments were conducted in order to gain a better understanding of a cell's selectively permeable membrane and the passive processes of simple and facilitated diffusion. The purpose of this experiment was to make observations based on the computerized simulation providing information on the passage of water and solutes through semiprivate membranes, which may be applied to the study of transport mechanisms in living membrane- bounded cells. We hypothesized that when the sucrose concentration will change, the mass will also change. Introduction: A molecular composition of a plasma membrane is selective about what can passes through.
Diffusion lab report - have your Research Paper Done
Weigh and record initial weight, place in cup of distilled water for 20 minutes. Preparing dialysis Bag: Methods Continued, chemical Indicators: Controls: Test the stock solution to indicate what is already present. Silver Nitrate - cloudy white is positive for chloride ions. Iodine - purplish-black is positive for starch and, benedict's solution - starts yellow going towards more reddish orange for glucose. Experimental Tubes: Test the distilled water after 20 minutes.
Results: Final weight of dialysis Bag:.6 grams Percent Change.6 -.5 /.5 x 100.6 What happened? Solution outside the cell was Hypotonic The dialysis bag gained weight Silver Nitrate and Benedict's solution tested positive for the Experimental tubes, iodine home tested negative. water entered cell -Chloride ions and Glucose diffused through membrane; starch did not. Only certain molecules can pass through semirmeable membranes. Distilled Water Clip dialysis Membrane Stock solution Clip Silver Nitrate iodine benedict's Works Cited Lab Manual ology-online.
Explain Osmosis in different types of solutions. Osmosis- diffusion of water across a semi-permeable membrane. Semi-permeable- being only permeable to certain molecules and not all molecules; selectively permeable. Hypotonic- solute concentration lower in the solution than in the cell. Hypertonic- solute concentration higher in the solutioin than in the cell.
Isotonic- solute concentration the same in the solution and in the cell. Determine what molecules diffused through the membrane into the solution by using chemical indicators. Water is moving into the bag from low to high concentration. Materials, one plastic cup, one piece dialysis tubing, two clips. Stock solution (water, salt, sugar, starch). Large beaker, six test tubes and test tube rack. Hot water bath, silver Nitrate (Chloride ions iodine (Starch). Benedict's solution (Glucose methods, open dialysis tubing, seal with clip. Through open end, fill with stock solution.
Experiments for, diffusion and Osmosis, lab, report
Another variable that could be improved would be to use graduated cylinders in order to measure the amount of solution/distilled water is to be measured for each dialysis tube. Another way of conducting the experiment is to use the same solution/distilled water for each of the beakers and fill each dialysis tube with the four different solutions). Osmosis and, diffusion, lab, results, hypothesis, the bag weight will increase. Objectives, background, diffusion - spontaneous movement of particles from an area of high concentration to an area of low concentration. Experiment, determine the movement of molecules when really a dialysis bag with a high concentration of solutes is placed in a solution with a low concentration of solutes. Explain concepts of, diffusion and Osmosis. Test for the movement of molecules using indicator chemicals.
However since the data had shown only hyper-tonic reactions, more trials will need to be conducted in order to fully collect the data and support the hypothesis. Are there any potential errors within the experiment? There is potential for many different errors within the experiment. One potential error is the size of each dialysis tube being submerged within each beaker. Another possible error would be the amount of solution poured to each beaker. Other errors include massing the dialysis tube before filling it up with liquid or the amount of liquid needed to fill up each dialysis tube equally. How can the experiment essay be improved? One improvement to the experiment would to have a controlled variable within the experiment.
the data say? According to our data, all the beakers caused the dialysis tubes to lose their mass and decrease in volume as a result. Because each tube has lost mass, that means each tested solution must be hyper-tonic. However since almost each dialysis tube has lost a different amount of mass, then the concentration of each solution is different. Since the concentration of the solutions are different, then Solution Y (blue) would be the most hyper-tonic solution, then Solution Z (orange solution X (clear and Solution W (yellow) being the least hyper-tonic (or possibly isotonic. does the data support our hypothesis? Since the dialysis tube has changed with the different solutions affecting it, then our data supports our hypothesis since the mass of each solution has changed.
All three membranes reached equilibrium in 10 minutes at an average diffusion rate.0150mM/min. Albumin molecules diffused through any of the four membranes teste. Nacl molecules moved down its concentration gradient and into the beaker filled with report deionized water thus resulted in diffusion. Urea showed no diffusion occurring with all four membranes. Glucose diffused through the 200 mwco membranes only, it was too large to pass through the rest of the mwco membranes. Activity 2: Simulating Facilitated, diffusion, results: Facilitated, diffusion, results (glucose transport rate, mM/min) Glucose concentration (mM) . Of glucose carrier proteins.00 .0008 .0010 .0012 .00 .0023 .0031 .0038.
Diffusion lab report - academic Papers Writing Help you
The importance of this computerized simulation study was to gain an understanding of the professional processes that account for the movement of substances across the plasma membrane, and to indicate the driving force for each. This may also be applied to the study of transport mechanisms in living membrane-bounded cells. Also, understanding of which way substances will move passively through a deferentially permeable membrane depending on the concentration differences. We used PhysioEx software to examine. In these experiments we used different sized membranes as well as nacl, urea, glucose, albumin, powdered charcoal, and KCl. The step by step process was used by the software so that we could see the different kinds. The pore sizes of mwco utilized in this experiment for the four members were 20, 50, 100 and 200. Nacl, Urea, albumin, and Glucose were the solutes tested in this experiment. The membranes of 50,100, and 200 (mwco) did allow the nacl to pass through.