Saturday, October 19, 2019

Osmosis Lab Report Example | Topics and Well Written Essays - 1000 words

Osmosis - Lab Report Example Cells require the movement of the chemicals inside and outside the cell for their survival. Cells require the movement of mainly the solute and solvent molecules inside and out of the cells for their proper functioning. The movement of the molecules occurs by active and passive processes. If the cell uses ATP for the transport of the molecules then it is termed as active process and if the molecules crosses the membrane with the help of concentration gradient, then it is called as passive process. Simple diffusion, facilitated diffusion and osmosis are the types of passive process. Osmosis is the movement of water molecules from a lower solute concentration to the higher solute concentration through a permeable membrane. Water molecule is much smaller than most of the solute molecules. Thus they are able to move through the membranes in which the solute molecules cannot pass through. This property of the water molecule is called as osmosis. The cell membranes are more permeable to the water molecules than most other solvents. As a result the cell membrane allows most of the water molecules to penetrate inside the cell. This results in the hypotonic condition of the cell. As a result the cell swells. Sometimes the solute concentration will be higher outside the cell membrane and as a result, the cell looses its water molecules out. This results in cell shrinkage termed as hypertonic solution. Is there is no change in the solute concentration inside and outside the membrane, then the solution is said to be isotonic. Osmosis is very essential for the biological systems. The biological membranes are semi permeable in nature. Water molecules travel through the plasma membrane by diffusing across the phospholipid bilayer using the transmembrane proteins. Cellophane membrane is a type of partially permeable membrane that can allow the water molecules to pass through. Cellophane membrane is made by regenerating the cellulose b y the addition of some chemicals like alkali, carbon disulfide and sulfuric acid. Cellulose is derived from the wood, hemp and cotton. The Glucose molecules are larger than the water molecules and they don’t diffuse through the cellophane membrane. When the different glucose concentrations are kept separated by the cellophane membrane, the movement of the solvent molecule, (i.e.) the water molecules, from the region of higher concentration to the region of lower concentration occurs. The thermodynamic property of the solution to reach the equal concentration in both sides of the membrane takes place. Materials required: 4 finger bowls 4 pieces dialysis membrane 8 pieces string Metric ruler Hot plate Glass stirring rod Test tubes 50% glucose solution Squeeze bottle of distilled water Paper towels Electronic scale Boiling beads Plastic pan Dropper bottle of Benedict’s solution. Beakers of varying size ( 200 ml, 500 ml, 1000 ml) Pipettes Graduated cylinder ( 10 ml, 25 ml) Distilled water. Method: The 4 cellophane membranes are made active by dipping it in the distilled water. The membranes become wet and flexible. From the stock 50% glucose solution, the appropriate concentration of glucose solutions is prepared by diluting them appropriately with the distilled wat

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