What is osmotic tolerance?
The ability of bacteria to tolerate osmotic pressure fluctuations imposed at different rates or frequencies could be tested via chemostat culture. In their natural habitats, many bacteria grow on surfaces as biofilms.
What is meant by osmotic effect?
The osmotic effect causes a flow of water from the weak solution to the strong solution. Thus water on the outside of concrete (almost pure, i.e., a weak solution) is drawn into the pores where there is a stronger solution.
What is osmotic barrier?
Osmosis is a biophysical phenomenon occurring commonly in biologic systems, in which cells of fluid compartments are separated by semipermeable membranes. Osmosis describes the diffusion of the solvent through a semipermeable membrane. In contrast to solvent, solutes cannot pass this barrier. …
What is osmotic method?
In normal osmotic processes, solvent flows across a semipermeable membrane from a dilute solution to a more concentrated solution until equilibrium is reached. Solvent flows from the concentrated solution, leaving an even higher concentration of solute.
What type of stress is called osmotic stress?
Osmotic shock or osmotic stress is a sudden change in the solute concentration around a cell, causing a rapid change in the movement of water across its cell membrane. Under conditions of high concentrations of either salts, substrates or any solute in the supernatant, water is drawn out of the cells through osmosis. (
What is osmotic stress in yeast?
Then yeast cells experience a hyperosmotic shock (or osmotic upshift), accompanied by rapid water outflow and cell shrinking. Such a hypo-osmotic shock (or osmotic downshift) increases the water concentration gradient and leads to rapid influx of water, cell swelling, and hence increased turgor pressure.
Is osmosis active or passive?
Osmosis is a passive form of transport that results in equilibrium, but diffusion is an active form of transport. 2. Osmosis only occurs when a semi-permeable membrane is present, but diffusion can happen whether or not it is present.
What is the principle used in osmotic shock?
Osmotic shock is the technique of weakening cells caused by lysis, which is brought about by increased internal pressure as water rapidly enters cells when cells are subjected to high osmotic pressure followed by sudden dilution (Middelberg, 1995).
What is osmotic stress in plants?
Osmotic stress, caused by either drought, salinity, or cold stress, is one of the important abiotic factors which had a great impact on plant evolution. Osmotic stress in its broadest sense encompasses both drought and salinity stress-induced lowering of water potential in plant cell (Hoffmann 2002).