Diffusion and Osmosis

Kinetic energy is

the movement of molecules bumping into and rebounding off each other and moving in new directions.

Kinetic energy results in . . .

diffusion

Diffusion

the random movement of molecules from an area of higher concentration to an area of lower concentration.

Dynamic Equilibrium

Both areas will have approximately equal concentration and no net movement from one area to another will occur, although the particles will still be in motion

Osmosis

the passive transport of water across a semi-permeable membrane to balance the solute concentration without having to move solutes themselves

Hypertonic

higher solute concentration

Hypotonic

Lower solute concentration

Isotonic

The same/equal concentration of solute

These forms of transport do not need any added energy and have molecules only move from regions of lower to higher concentration during. . .

Osmosis and diffusion

The end result of osmosis should be. .. 

equilibrium

During osmosis, water molecules diffuse through the membrane from a region of _____ water potential to an area of ______ water potential until equilibrium is reached

higher, lower

Cells must often absorb molecules from

regions in which the concentration of the molecules may be lower than the concentration already the cell. ex) glucose

active transport

the movement of substances through the cell membrane against a concentration gradient.

Active transport involves

proteins in the cell membrane and energy derived from ATP

Dialysis

The movement of a solute thru a selectively permeable membrane

Dialysis Tubing is made of

a membrane containing tiny pores.

The size of pores determines the size of molecules that can pass through. _____ solute molecules can pass through freely, but ____ molecules will pass through more slowly or not at all.

Small, large

A 0.5 M sucrose solution is ________ to a 0.1 M sucrose solution.

hypertonic

A 0.5 solution is ___ to a 1.0 M solution

hypotonic

Two 0.1 M solutions are _____ to each other

isotonic

For Osmosis, equilibrium means . . .

the solute levels are equal, not necessarily the water potential. 

• A solution can have more water on one side and less water on the other if the concentration of the particles is equal

Water potential

In the context of osmosis, it means the amount of water in an area of a solution

Water always moves from ____ to _____

hypotonic to hypertonic

Hypotonic in water means

higher water potential, meaning more water, and less solutes

Hypertonic in water means

lower water potential, meaning less water, and more solutes

In a hypotonic solution. . .

water will move into the cell

In a hypertonic solution . . .

water will move from the cell into the surrounding solution

In a isotonic solution . . .

there will no longer be any net movement for the water in or out of the cell

Soaking helps to . . .

open up the dialysis membrane

Starch is indicated by

the formation of a dark-bluish color with iodine

Glucose is indicated by

change in color of indicator strip