Activity 3 Prelab_membrane Transport

Activity 3: Membrane Transport Pre-Lab Discussion

HOMEOSTASIS  Dynamic

maintenance of a constant internal environment  Necessitates the entry and exit of substances into or out of cells through the plasma membrane

TRANSPORT PROCESSES  Diffusion  Osmosis  Dialysis  Active Transport

DIFFUSION  Spontaneous intermingling of molecules of

different substances  Results from the inherent kinetic energy of the molecules  Movement of molecules is from an area of HIGHER concentration to LOWER concentration

OSMOSIS  Special form

of diffusion  Movement of water BUT NOT SOLUTES across a membrane  Movement of water molecules from a hypoosmotic (dilute) solution to a hyperosmotic (concentrated) solution

DIALYSIS  Pressure induced diffusion of some

solutes across a membrane  Movement occurs from an area of HIGHER PRESSURE to an area of LOWER PRESSURE

ACTIVITY 3.A.1: Diffusion

ACTIVITY 3.A.2: Diffusion

ACTIVITY 3.A.2: Diffusion

DIFFUSION AND TEMPERATURE

DIFFUSION AND MOLECULAR SIZE

OSMOSIS

OSMOSIS AND RBC A 0.9% NaCl

B dH2O

C 5% NaCl

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