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Osmosis Lab

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Introduction: Water is the body’s prime solvent. In essence, the movement of water and solutes though cell membranes is an integral characteristic of physiology. Osmosis is a passive process that involves the movement of water across a membrane down a concentration gradient (Marieb, 2012). If a cell membrane is differentially, or selectively permeable, both water and solutes will move down their concentration gradients. Conversely if a cell membrane is impermeable, only water can move across it down a concentration gradient (Marieb, 2010). Varying osmotic gradients can affect the volume of a cell when it is placed in solutions of different concentrations. Hence, osmosis affects tonicity, which is a concept that refers to the way the movement …show more content…
If the concentration of impermeable solutes is the same inside and outside of the cell, the solution is isotonic, meaning the movement of water will be equal and the cell maintains its original shape. If there is a higher concentration of impermeable solutes outside the cell than in the cell’s interior, the solution is hypertonic. Because the net movement of water would be out of the cell, the cell would shrink, through a process of crenation in a hypertonic solution (Marieb, 2012). If the concentration of impermeable solutes is lower outside of the cell than in the cell’s interior, then the solution is hypotonic. The net movement of water would be into the cell, and the cell would swell and possibly burst, a phenomenon referred to as hemolysis (Marieb, …show more content…
Add a small drop of deionized water using the medicine dropper to the sheep’s blood on the slide. Slightly tilt the slide to mix and cover with a clean cover slip. Place the prepared slide under the high power lens of the microscope and immediately observe the shape of the red bold cells. Record any observations. Repeat the above procedure two more times, preparing wet mounts of sheep’s blood using 0.85% NaCl solution, and then using 10% NaCl solution as the suspending mediums. Carefully observe the red blood cells, after waiting a few minutes timed by the timer, for both wet mounts under the high-power lens of the microscope. Record any

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