Introduction: All cells contain membranes that are selectively permeable, allowing certain molecules to pass into the membrane as well as block the transport of large molecules from entering. The membrane serves as a barrier to separate the cell and its ‘environment. Without the cell membrane, the substances necessary to the life of the cell would diffuse to the cell’s surroundings, causing toxic materials to enter into the cell. The diffusion of the solutes is limited by the semipermeable membrane. Diffusion is the movement of ions or molecules from an area of higher concentration to an area of lower concentration. Diffusion proceeds until the two concentrations are equal. For example, if a lump of sugar is dropped into a beaker of …show more content…
If blood cells are placed in contact with a hypotonic solution, the water will flow into the cell, increasing hydrostatic pressure or turgor pressure. The turgor pressure results in the hemolysis of red blood cells. In an animal cell, the cell will burst due to the lack of having a cell wall. In a plant cell, the cell will remain in normal condition due to the cell wall protecting the shape of the cell. A hypertonic solution is when there is a higher concentration of solute in the environment. If blood cells are placed in contact with a hypertonic solution, the water will flow out of the cell, which results into dehydration. Eventually, the red blood cells will shrivel and become crenate. Plasmolysis in plant cells will occur if they are placed in a hypertonic solution. Plasmolysis is when the cell membrane pulls away from the cell wall. An isotonic solution is when there is an equal concentration of solute. Thus there is no net movement of water.
Hypothesis: If a potato core is placed in a hypertonic solution, then the potato core will decrease in size whereas the potato core will increase in size when placed in a hypotonic solution.
Materials and Methods Salt concentrations of 0%, 0.9%, 5%, 10%, and 15% were prepared before the experiment. In the experiment, the independent variables is the salt concentration and the dependent variable is the weight of the potatoes. These different solutions are used to indicate
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.
My prediction is that as the concentration increases, the potato cell will lose more weight. This is because of the osmosis of water particles from the potato cell cytoplasm to the solution, resulting in a loss of weight. As the concentration decreases, the potato will lose less weight until a certain point where the osmosis of particles in and out of the potato cells will be equal. I also predict that as the salt
Purpose: To determine the concentration of solute in the potato’s cytoplasm by measuring the change
7. Explain how incubation plant tissues in a series of dilutions of sucrose can give an
Finally, it could also be a hypertonic solution which is when there is a higher concentration of solute in the solution than in the cell and therefore the water leaves the cell. This make the cell plasmolyzed or “shrunken”. In our experiment this means that the potato cell would
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
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
A cell needs to perform diffusion in order to survive. Substances, including water, ions, and molecules that are required for cellular activities, can enter and leave cells by a passive process such as diffusion. Diffusion is random movement of molecules in a net direction from a region of higher concentration to a region of lower concentration order to reach equilibrium. Diffusion does not require any energy input. Diffusion is needed for basic cell functions - for example, in humans, cells obtain oxygen via diffusion from the alveoli of the lungs into the blood and in plants water
The diffusion across a cell membrane is a process of passive and spontaneous net movement of small lipophilic molecules. The molecules move from a high concentration to a low concentrated region along the concentration gradient. The result being a point of equilibrium, this is where a random molecular motion continues but there is no longer any net movement. However, there are things that can affect the rate of diffusion, these being temperature, surface area, concentration, size of the molecule, permeability, diffusion distance and concentration difference. Osmosis is a type of diffusion as it is the movement of water molecules through a semipermeable membrane into a region of higher solute concentration. Equilibrium is reached when the solute concentration is equal on both sides. Water potential is measured in kiloPascals, it is the measuring of the concentration of free water molecules that are able to diffuse compared to pure water, which is 0 kilopascals. It is a measure of the tendency of free water molecules to diffuse from one place to another. The result being, the more free water molecules, the higher the Water Potential. However, Water potential is affected by two factors: pressure and the amount of solute.
Cells are always in motion, energy of motion known as kinetic energy. This kinetic energy causes the membranes in motion to bump into each other, causing the membranes to move in another direction – a direction from a higher concentration of the solution to a lower one. Membranes moving around leads to diffusion and osmosis. Diffusion is the random movement of molecules from an area of higher concentration to an area of lower concentration, until they are equally distributed (Mader & Windelspecht, 2012, p. 50). Cells have a plasma membrane that separates the internal cell from the exterior environment. The plasma membrane is selectively permeable which allows certain solvents to pass through
All cells contain membranes that are selectively permeable, allowing certain things to pass into and leave out of the cell. The process in which molecules of a substance move from an area of high concentration to areas of low concentration is called Diffusion. Whereas Osmosis is the process in which water crosses membranes from regions of high water concentration to areas with low water concentration. While molecules in diffusion move down a concentration gradient, molecules during osmosis both move down a concentration gradient as well as across it. Both diffusion, and osmosis are types of passive transport, which do not require help.
I think that when the potatoe is placed in a salt concentration where the water potential is greater the potatoe molecules will move from the potatoe to the salt and a decrease in the mass will happen. The more salt there is in the water the fresher the potatoe will stay. The
In the Potato Core Osmosis Lab, the main purpose of the experiment was to test the different amounts of corn syrup on potatoes. A variety of potatoes were distributed and placed into unknown amounts of corn syrup which range from no corn syrup to 100% corn syrup. Then the following day, the results were recorded on the size of the potato. Results stated that as the amount of syrup increased, the smaller the potato got. The hypothesis stated that if the potatoes were placed in a high percent of syrup, then it would shrink, which corresponds to the results causing the hypothesis to be supported.
In animal cells, the movement of water into and out of the cell is influenced by the relative concentration of solute
Then, each group of students received the necessary materials to complete the experiment. When the students received the cups, they labeled cups to distinguish between the salt solution, distilled water, and control group. After weighing the cups and finding the mass of the cucumbers, the students poured 50 ml of water in one cup, 50 ml of salt solution in the other, and left the control cup empty. Then, the students placed the cucumbers into the cups and waited 30 minutes for the results. After the 30 minutes, the students removed the cucumbers from each solution and dried the cucumbers with paper towels. The students then weighed the cucumbers again and recorded their results. Lastly, the students found the difference from the original mass of the cucumbers and recorded their results.