Abstract:
The main purpose of the experiment was to test the idea that water would move from the higher concentration to the lower concentration. In order to test this theory, we placed potato slices in 7 different containers, each containing different concentrations of NaCl, to measure the weight change from osmosis. The containers ranged from 0M NaCl all the way to .6M NaCl. We measured the potato slices before and after placing the slices in the solutions and recorded the net change in weight to determine the tonicity of the potato cells. Our results showed that the potato slices put in a NaCl solution of .2M or higher lost weight and the potato slices put in a NaCl solution of .1M or lower gained weight. This shows that the osmolarity of the potato falls within the range of .1M to .2M, and it also proves the process of Osmosis by having the higher concentration move to the lower concentration. In addition to this, it can be concluded that the osmolarity of cells can be determined by observing the affects of osmosis.
Introduction:
Osmosis can be defined as the force that drives the movement of water due to differences in solute concentration. The process involves the random movement of molecular water molecules through a semi-permeable membrane from regions of higher concentration to regions of lower concentration until both regions equal out (Ledbetter 2013, Ness 2013). Polar substances such as glucose and salts cannot travel through the cell membrane, which
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.
Van’t Hoff’s Law suggests that the osmotic potential of a cell is proportional to the concentration of solute particles in a solution. The purpose of this experiment was to determine if there are any differences between the osmolalities, the no-weight-changes of osmolalities, and the water potentials of potato cores in different solutions of different solutes. The percent weight change of the potato cores was calculated through a “change in weight” method. The potato core’s weight was measured before and after they were put into different concentrations of a solute for 1.5 hours. In our experiment, there were no significant differences from the osmotic potentials of our results and the osmotic potentials of other scientists work. Ending with chi square values of 2.17 and 2.71, and p values of 0.256 and 0.337, concluding that there is no difference in water potentials of potato cores in different solutions of different solutes at varying concentrations.
Osmosis: Osmosis is the movement of fluid from an area of lesser concentration to an area of greater concentration of solutes. Glucose is added to the dialysate and creates an osmotic gradient across the membrane, pulling excess fluid from the blood.
The osmotic concentration was determined by measuring the percent change in mass of the potato cylinders. Change in mass was measured of seven solutions, each containing different levels of concentration 0, 0.1, 0.2, 0.3, 0.4, 0.5, and 0.6M. The percent change in mass decreased as sucrose concentration increased, therefore, relative osmotic concentration also decreased as sucrose concentration increased. However, the osmotic concentration of 0.3 M sucrose solution was relatively greater than that of 0.2 M sucrose solution. In sucrose concentration 0.6 M, the osmotic concentration decreased almost double from that of 0.5, and significantly from those of all other sucrose concentrations. The osmotic concentrations were greater than zero in sucrose solutions of 0, 0.1, 0.2, and 0.3 M; these cells were hypotonic, meaning the potato had more solute. The osmotic concentrations were less than zero in sucrose solutions of 0.4, 0.5, and 0.6 M; these cells were hypertonic,
Osmosis is defined as the tendency of water to flow through a semipermeable membrane to the side with a lower solute concentration. Water potential can be explained by solutes in a solution. The more positive a number is more likely it will lose water. Therefore should water potential be negative the cell the less likely it will lose water. In using potatoes the effects of the molarity of sucrose on the turgidity of plant cells. According to Clemson University, the average molarity of a White potato is between .24 M and .31 M when submerged in a sorbitol solution. This experiment was conducted with the purpose of explaining the relationship found between the mass in plants when put into varying concentrations of sucrose solutions. Should the potatoes be placed in a solution that contains 0.2M or .4M of sucrose solution it will be hypotonic and gain mass or if placed in .6M< it will be hypertonic and lose mass instead. Controlled Variables in this lab were: Composition of plastic cups, Brand of Russet Potatoes, Brand of Sweet Potatoes and the Temperature of the room. For independent variable that caused the results recorded it was the different Sucrose concentrations (0.0M, 0.2M, 0.4M, 0.6M, 0.8M, 1M). The dependent variable was the percentage change from the initial weighs to the final. The cup with .4 molarity was the closest to an isotonic solution and was used as the control group for the lab. Water potential is the free energy per mole of water. It is
Osmosis is the "net movement of water molecules from an area of high water potential to an area of low water potential through a partially permeable membrane." The diagram below illustrates the process of osmosis. (See Figure 1)
Osmosis is the movement of water molecules from high concentration to low concentration through semipermeable membranes, caused by the difference in concentrations on the two sides of a membrane (Rbowen, L.). It occurs in both animals and plants cells. In human bodies, the process of osmosis is primarily found in the kidneys, in the glomerulus. In plants, osmosis is carried out everywhere within the cells of the plant (World Book, 1997). This can be shown by an experiment with potato and glucose/salt solution. The experiment requires putting a piece (or more) of potatoes into glucose or salt solution to see the result of osmosis (a hypertonic type of solution is mostly used as it would give the most prominent visual prove of
Osmosis is a special type of diffusion. It is the diffusion of water molecules across a semipermeable membrane (a membrane that allows for the diffusion of certain solutes and water) from an area of higher water concentration to one of lower water concentration. For example, if a 1 M aqueous starch solution is separated from a .5 M aqueous starch solution by a semi-permeable membrane, then water molecules will move from the .5 M aqueous starch solution (higher water molecule concentration) toward the more concentrated 1M starch solution (lower water molecule concentration) until an equilibrium of water molecules exists between the two solutions. Since the semi-permeable membrane did not allow for the passage of starch molecules, the 1M-starch solution will gain in volume as the water moves in (Figure 3).
An investigation of the glucose concentration of the cell sap in potato cells In this experiment I intend to investigate the effects of osmosis on potato cells. Specifically, I intend to use my knowledge of osmosis to investigate the glucose concentration of the cell sap in potato cells. Osmosis is a method by which water levels on either side of a semi permeable membrane may balance themselves. It occurs between regions of high water concentration and low water concentration.
Within every cell, a movement of a solvent occurs through a semipermeable membrane to equalize the concentration of solute on both sides of the membrane. The diffusion of water across the cell’s membrane down to its concentration gradient is called osmosis. In this case, the concentration gradient is the difference of density between one side of the cell membrane to the other. Since the cell’s membrane is permeable, particles can flow freely in and out of the cell, but the net flow will be strong in the direction of lower concentration until the system has reached a stage of equilibrium, the point at which both sides of the membrane are equal. In the
Osmosis is the passive movement of water from an area of low solute concentration to an area of high solute concentration, normally across a membrane which prevents the movement of solvent. This is a process by which materials may move into, out of, or within cells. Osmosis doesn’t depend on energy provided by living organisms but is affected by the properties of the cell membrane. The rate of osmosis is dependent on such factors as temperature, pressure, molecular properties such as size and mass, and the concentration gradient. In osmosis, the relationship between a solute’s concentration outside of cell and inside of a cell is described in terms of the tonicity of the solution outside of the cell. A cell is in a hypotonic solution when the solute is more concentrated inside the cell and therefore water moves into the cell. In this solution the cell swells as water enters, this may continue until it ruptures or hemolyzes. In the reverse condition, the cell is in a hypertonic solution
Osmosis is a natural occurrence constantly happening within the cells of all living things. For osmosis to occur, water molecules must move across a semipermeable membrane from an area of low concentration to an are of high concentration. In order to understand osmosis, people must understand the different types of concentrations that can be present within solution. One of them is an Isotonic solution where the concentration of dissolved particles is equal to that of a cell’s. Another is a hypertonic solution where there is a higher concentration of dissolved particles then inside the cell. And lastly there is a hypotonic solution where there are less dissolved particles than inside the cell. As dissolved particles move to a region of lower concentration, water moves the opposite direction as a result of there being less water in the highly concentrated region. In this experiment, gummy bears were placed in salt water, sugar water, and tap water to find the measure of osmosis between the solution and gummy bear.
In this experiment, the osmotic concentration is found with potato slices placed in sucrose solutions. Osmosis in this model is the net movement of water between the potato cell and the sucrose solution. The movement of water is determined by the molarity of sucrose. As the molarity of sucrose increased then the concentration in the solution also increased. H2O will move through the cell membrane to areas of higher concentration in order to reach equilibrium. If cells are placed
Abstract The purpose of this experiment is to observe the osmosis process in which molecules of a solvent pass through a semipermeable membrane. This experiment is conducted to find out which kind of osmosis process is taking place in each of the three experiments. The sheep’s blood is placed into three different types of solutions. These solutions have increased concentrations of NaCl.
Osmosis is the diffusion of water across a membrane to create an equilibrium between the levels of concentration of a solute both inside and outside the cell. In this case the solute will be sugar as the potato core will be immersed in sucrose solution.