Diffusion and Osmosis

Diffusion

Movement of particles or molecules from an area of high concentration to an area of low concentration

Osmosis

Diffusion of water across a selectively permeable membrane

Selectively pemeable membrane

A membrane that allows certain materials to pass through, but not others

Tonicity

A description of the relative solute concentration in a solution as compared to another solution.

Equilibrium

The condition that exists in system when there is a relatively equal distribution of a particular molecule

Hypertonic

A solution that has a higher concentration of solutes than another.

Hypotonic

A solution that has a lower concentration of solutes than another.

Isotonic

Two solutions that have an equal concentration of solutes.

Solute

substance that is dissolved in a solution

Solvent

the liquid that contains the dissolved solute in a solution.

Cell Membrane

regulates and controls what enters or leaves the cell

Facilitated Diffusion

this form of diffusion is regulated by protein channels in the membrane and requires no energy input from the cell

Active Transport

movement of molecules or ion into or out of the cell against its concentration gradient (from low to high) and requires an input of energy.

Endocytosis

movement of substances into the cell by creating a new vacuole at the cell membrane. requires energy.

Exocytosis

movement of substances out of a cell by merging a vacuole with the cell membrane. requires energy.

Hypertonic

the left side is _ compared to the right side.

Hypotonic

The right side is _ compared to the left side.

right, left, osmosis

Water will move from the to the by _.

Hypotonic

The left side is _ compared to the right side.

Hypertonic

The right side is _ compared to the left side.

left, right, osmosis

Water will move from the to the by _.

Cell Membrane

Composed of a phospholipid bilayer

Phospholipid

molecule that makes up cell membranes. It has a hydrophilic "head" and two hydrophobic "tails".

Hydrophilic

water loving. substances that easily mix with water.

Hydrophobic

water hating. substances that will not mix with water.

Transport Protein

Proteins within the cell membrane that function to move substances into or out of the cell.