Osmosis and Cell

Cells and molecules in the environment are constantly moving and changing, for cells to function properly there is a need for equilibrium to be met. The size of the cell and the solution outside of the cell affects the rate of diffusion and osmosis in the cell. Cells are constantly trying to reach an equilibrium with the molecules and substances around it, which is why there are such terms as: hypertonic, hypotonic and isotonic. The procedures allowed testing of whether or not surface area or volume increased diffusion and how different substance control diffusion. Cells are constantly moving to reach equilibrium through diffusion and osmosis.

2. Explain your observations in detail in terms of concentration gradient, diffusion, osmosis, osmotic pressure, passive transport, and active transport.

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.

Independent Variable: The cell and its volume, surface area, and the water potential of the internal cell and its environment

The concentration of dissolved substances is less in the extracellular fluid than in the cytoplasm. Hypotonic Solution Concentration of dissolved substances (solute) Concentration of water (solvent) What happens to an animal cells? Inside the cell Greater Less Outside the cell Less Greater Membrane

Water diffuses across the membrane from the region of lower solute concentration (higher free water concentration) to that of higher solute concentration (lower free water concentration) until the solute concentrations on both sides of the membrane are equal. The diffusion of free water across a selectively permeable membrane, whether artificial or cellular, is called osmosis. The movement of water across cell membranes and the balance of water between the cell and its environment are crucial to organisms. ("Diffusion And Osmosis - Difference And Comparison | Diffen"). A semi-permeable membrane known as the cell membrane surrounds the living cells of both plants and animals. Both solute concentration and membrane permeability are taken into account in the ability of a cell to gain or lose water. If there is a higher concentration of solutes in the surrounding solution, water will tend to leave the cell, and vice versa. The membrane forms a selective barrier between the cell and its environment and does not allow toxic substances from the surroundings to enter into the cell (Deena T Kochunni). The selective permeability allows the cell to regulate the flow of necessary substances into and out of the cell. In plants osmosis is also responsible for absorbing water and minerals from the soil by using the semipermeable membrane of the root (Deena T Kochunni). If the extracellular fluid has a lower osmolarity than the fluid inside the cell, it’s said to be

Many molecules and hydrocarbons diffuse down the concentration gradient, moving from a high concentration to a low concentration. Without diffusion, osmosis cannot occur, osmosis is diffusion of water. During osmosis in animal and plant cells, tonicity, ability to cause a cell to gain or lose water, causes three different solutions, isotonic, hypertonic, and hypotonic. The purpose of the experiment

The 3 types of cellular transport that I am including are Osmosis, Active Transport, and Facilitated Diffusion. Osmosis allows water to move from a region of lower solute concentration to a region of higher solute concentration until both sides are equal. During Osmosis, only water molecules can pass through, and sugar molecules cannot pass through the membrane. This process requires no energy from the cell. An example of osmosis is in an hypotonic red blood cell, which will cause the cell to burst due to the cell having too much water. Cells can regulate water concentrations through osmoregulation. Active transport requires energy because it pumps solute against its concentration gradient. Energy for this work is usually supplied by ATP. To

Foor this you simply have to take a look at the processed data table and graph. There is a clear specific trend, visibly recognizable as well as mathematically (a trend line indicates it), that is, as the molar concentration (solute) of salt increased in the solution where potatoes were placed, the mass of potatoes decreased. Now, from the molar concentrations of salt solute that we tested (0.0M, 0.2M, 0.4M, 0.6M, 0.8M, 1.0M) we cannot decipher with certainty and accuracy what is the molar concentration of potato cells. However, we can estimate, and judging by the a decrease in percent mass from 21.10% grams (0.0M) to 12.13% (0.2M) and followed by a constant decrease in percent change in mass, it can be said that the salt concentration of a potato cell is between 0.0M and 0.2M. This is because these molar concentrations are the one that show the decrease in mass of the potato. When there’s a decrease in mass, this practically means that the water inside the cells is leaving because of diffusion to areas of lower concentration.

We then measured the distance from the origin to the solvent and also from the origin to

What is the relationship between solute concentration and the movement of water through a selectively permeabe membrane by the process of osmosis?

The idea behind this experiment is to know how does relative concentrations of solutes affect the direction of osmosis.  Osmosis is the diffusion of water through a membrane.  Apparently, for this experiment, the dialysis tube would play the role of a cell membrane since it contains small pores.  These pores would distinguish which liquids are permeable and which ones are not.  The liquids that are going to be used for this experiment includes sucrose solution and water.  My hypothesis and prediction for this experiment is that the dialysis tube that contains water in and water outside of it will not have a change in mass.  While the dialysis tube that contains water in and sucrose outside of it will eventually lose mass.  In addition, the

Data: Effect of Solute Concentration on Osmosis in Potato Cells (for the 6 groups of our class)

Understanding the diffusion of water into and out of the cell through osmosis is fundamental to the learning and teaching of biology (e.g. Cook, Carter and Wiebe, 2008).

By definition, Osmosis is the diffusion of a solvent, such as water, through a selectively permeable membrane (Pearson, pg. 70). Osmosis occurs whenever the water concentration differs on the two sides of a membrane. If distilled water is present on both sides of a selectively permeable membrane, no net osmosis occurs, even though water molecules move in both directions through the membrane. In addition, if the solute concentration on the two sides of the membrane differs, water concentration differs as well.