LAB 03 OSMOSIS, DIFFUSION AND TONICITY

Diffusion

Passive movement of a solute down its concentration gradient, from an area of higher solute concentration to an area of lower solute concentration.

Homeostasis

Maintenance of a constant internal environment via negative feedback loops.

Osmosis

Movement of water down its concentration gradient, from an area of higher water concentration to an area of lower water concentration.

Solubility

The ability of a substance to dissolve in a solvent.

Concentration

In a solution, the amount of solute dissolved in a given amount of solvent.

Tonicity

Refers to relative concentrations of two solutions, affecting the osmotic pressure and volume of a cell.

ICF

Inside the cell

ISF

Outside the cell

Isotonic

Solute concentration is the same inside and outside the cell; no osmotic pressure; no change in cell volume.

Hypertonic

Solute concentration is higher outside the cell, resulting in water movement out of the cell and cell shrinkage.

Hypotonic

Solute concentration is lower outside the cell, resulting in water movement into the cell and cell swelling or bursting.

Molecular weight (MW)

Number of grams in one mole of a substance, where 1 mole = 6.02 x 10^23 particles. Example: MW of water is 18 g.