The purpose of this lab is to test how molecular size and diffusion relate and to test the permeability of dialysis tubing using sucrose, glucose, starch and iodine. It is expected that potassium permanganate will travel a farther distance than the methylene blue because the permanganate has a smaller molar mass then the methylene, particles that are larger take more time to move than smaller particles do. In the second experiment it is anticipated that sucrose will increase in volume whereas the water will decrease in volume, this is due to osmosis of water particles and the selective permeability in the dialysis tubing. The second part of the experiment, which dealt with color change in iodine and sucrose, it is predicted that dialysis tube …show more content…
(Cliffnotes) Osmosis played a really big role in the second part of the experiment. One of the beakers was filled with water and so was one of the dialysis tubes and both reacted with sucrose. When particles move through the membrane, whether they go in or out, the cell will either begin to shrink or grow, and can grow so much that it bursts. If a solution gains water it is called a hypertonic to the solution on the outside. If the opposite happens then the solution is hypotonic. When an equal amount of water particles are transferred between both solutions then they are both called isotonic solutions. (Lab notes) Dialysis is the process in which particles, that are different sizes, are separated using a selectively permeable membrane. In the experiment we used the dialysis tubes to test the permeability of water, sucrose and …show more content…
The molecular size of the molecules affects the rate at which the molecule passes through the membrane. First we found the mass of Potassium permanganate (KMnO4), which has a molecular weight of 158.034 g/mol. Methylene Blue (C16H18N3SCl) whose molecular weight is much larger than the permanganate is 319.85 g/mol. The size of Methylene Blue is almost doubled that of Potassium permanganate. The distance traveled for Potassium permanganate was 3.5 mm in thirty minutes and Methylene blue traveled 3 mm over the same period of time. This shows that the smaller the particle, the faster it is for the molecule to pass through the semipermeable
Investigating the Concentration of Sucrose in Cells of Carrots and Potatoes Plan Introduction Osmosis is defined as 'the net movement of water molecules from a region of high water concentration to a region of lower water concentration through a partially permeable membrane'. In my experiment the process of osmosis will be due to the concentration of sucrose inside the cell compared to outside. Therefore if there is a higher concentration of sucrose molecules outside the cell then the net movement of water molecules will be out of the cell and similarly if there is a higher concentration of sucrose molecules inside the cell then the net movement of water molecules will be into the cell. This movement of water molecules causes the cells to become either turgid, which is when the cells are filled with water, or flaccid, which is when the cells are 'limp' with little water.
The chemistry test shows the levels of electrolytes found in the blood: sodium, potassium, chloride, phosphorus, magnesium and calcium. Imbalances in these electrolytes can cause complications, which especially in the case of potassium, can be deadly. Also shown by the chemistry test, blood urea nitrogen and creatinine levels can show how well the patient’s kidneys are functioning in filtering waste from the blood. Trauma and blood loss can affect how the kidney’s function not only in filtering waste, but also in acid-base balance, and balancing electrolyte levels. Another marker of kidney function is the glomerular filtration rate, which measures the rate filtrate is created by the glomerulus of the kidney (Winkelman, 2016). This is controlled by the kidneys themselves, meaning changes in the function of the kidneys can lead to an altered filtration rate (Winkelman, 2016). Lactic acid is measured by the chemistry test also, and an increase in lactic acid can signify acidosis caused by the lactic acid being formed by cells that do not have adequate oxygen to process glucose for energy (Workman, 2016). This decrease in available oxygen could be caused by damage to or impairment of the lungs. Carbon-dioxide, which is also measured by the chemistry test, can show
The Effect of Solute Concentration on the Rate of Osmosis Aim: To test and observe how the concentration gradient between a potato and water & sugar solution will affect the rate of osmosis. Introduction: Osmosis is defined as, diffusion, or net movement, of free water molecules from high to low concentration through a semi-permeable membrane. When a substance, such as sugar (which we will be using in the experiment we are about to analyse), dissolves in water, it attracts free water molecules to itself, and in doing so, stops them from moving freely. The effect of this, is that the concentration of (free) water molecules in that environment goes down. There are less free water molecules, and therefore less water molecules to pass across a semi-permeable membrane, through which sugar molecules and other molecules attached to them are too big to diffuse across with ease.
Osmosis Experiment Planning Aim: The main subject that I will be planning to investigate is the effects of a concentrated sucrose solution on potato cells on the basis of the Osmosis theory. Background knowledge: The plant cell and its structure To understand osmosis in detail I will need to explain the plant cell (which is the cell included in the osmosis experiment) and its cell membrane. Below I have a diagram of a plant cell: [IMAGE] Osmosis is about the movement of particles from a higher concentrated solution to a lower concentrated solution to create an ethical balance via a partially or semi permeable cell membrane. Osmosis in simple terms is the exchange of particles between the cytoplasm inside the cell and the solution outside the cell. What makes this exhange is the partially permable cell membrane.
molecules go in and out of the cell. There is no net movement of water
The Effect of Changing the Concentration of Sucrose on the Movement of Water into a Potato
If the concentration of sucrose increases, then the mass of the potato will decrease. However, if the concentration of the solution in the beaker is less than that of the potato (such as distilled water), then the mass of the potato will increase. So, as the concentration of sucrose increases the rate of osmosis increases.
the same way as it does potato. I would also widen the range of sugar
Dialysis depends on dispersion amid which the portability of solute particles between two fluid spaces is confined, for the most part as indicated by their size. (In infrequently utilized adaptations of dialysis, confinement of dissemination by means of
- The nurse’s mistake will increase the saltiness due to the double amount of saline in the bag.
The liquids used were distilled water, and a starch solution, in line with the guiding question. Dialysis tubing was used because it performed similarly to an actual cell while being visible to the naked eye. First, I soaked four strips of dialysis tubing in water for 5 minutes, afterwards I knotted off one of the ends for all of the tubing. After, I filled two with a half tablespoon of distilled water, and another two with half a tablespoon of the starch solution. Next I measured the lengths, widths, and weights of the cells. I proceeded to leave the four cells to soak in distilled water for about 24 hours. After leaving them in distilled water for about a day, I extracted the cells from the distilled water and remeasured the measurements mentioned before. In hindsight, this was an ideal method to investigate the guiding question because the dialysis tubing functions almost identically to a living cell while being easier to observe and handle at the
Investigating Osmosis In A Potato Introduction: "Osmosis is typically defines as the flow of one constituent of a solution through a membrane while the other constituents are blocked and unable to pass through the membrane. Experimentation is necessary to determine which membranes permit selective flow, or osmosis, because not all membranes act in this way. Many membranes allow all or none of the constituents of a solution to pass through; only a few allow a selective flow. In a classic demonstration of osmosis, a vertical tube containing a solution of sugar, with its lower end closed off by a semi-permeable membrane, is placed in a container of water. As the water passes through the membrane into the tube, the level of sugar solution in the tube visibly rises.
Investigation of the Concentration and the Effect of Sucrose on Osmosis in Apple and Potato Tissues
== = This experiment is based on the concept of Osmosis. Osmosis is the diffusion of water molecules from a region of high water concentration to a low water concentration through a semi permeable membrane (in this case, the cell potato cell membrane). The cell walls of the potato cells are semi permeable meaning that water molecules (which are small) can fit through but other bigger molecules such as glucose cannot pass through. The water molecules can flow both ways through the membrane, letting molecules both in and out.