Osmosis

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Submitted By sthom23
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In an isotonic environment, solute concentration and water are equal inside and outside the cell. Water goes in and out of the cell at an equal rate. With a hypotonic environment, the water concentration is greater outside the cell, with solute concentration higher inside. Water moves into the cell. In a hypertonic environment, water concentration is greater inside the cell, with the solute concentration higher outside the cell. Water moves out of the cell. Microbe’s reaction to the changes in osmotic pressure determines their viability in the environment.
Isotonic or slightly hypotonic environments usually are best for optimal growth of bacteria. Some microbes can survive in different osmotic conditions and can survive in hypertonic conditions like salt water. They have adapted to the changes in osmotic conditions. Staphylococcus. Epidermidis in 1% NaCl solution had a large amount of growth and the solution was slightly cloudy, 4% NaCl solution had moderate growth, 10% NaCl solution had a small amount of growth. Saccharomy cerevisiae in 1% NaCl solution had a moderate amount of growth with the solution cloudy throughout, in 4% NaCl solution with minimal growth with the growth adhered to the side of the tube, scant amount of growth in the 10% NaCl solution. The test showed that S. epidermidis and S. cerevisiae can grow in concentrations of NaCl because both have adapted to the effects of NaCl in response to the osmotic pressure. The higher concentrations NaCl had the least amount of growth in both specimens. Staphylococcus epidermidis 1% sucrose solution= small amount of growth, 4% sucrose solution= moderate amount of growth, 10% sucrose= large amount of growth, Saccharomy cerevisiae 1% sucrose solution= scant amount of growth, 4% sucrose solution= moderate amount of growth, 10% sucrose solution= large amount of growth. S. epidermidis and S. cerevisiae…...

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