Methods of Movement of Solutes Flashcards
The tendency of molecules of ions to move from an area where they are in higher concentration to an area where they are in lower concentration.
Diffusion
During diffusion, when molecules or ions move to a lower concentration from its higher concentration, they are moving
Down their concentration gradient.
Because the driving force for diffusion is the kinetic energy of the molecules themselves, the speed of diffusion is influences by molecular ____ and by ____.
Size (the smaller, the faster)
Temp (the warmer, the faster)
When a uniform mixture of molecules is achieved, the system reaches
Equilibrium
The plasma membrane is a physical barrier to Free Diffusion because of its hydrophobic core. However, a molecule or ion will diffuse through the membrane if the molecule is ____, _____, _______.
- lipid soluble
- small enough to pass through the membrane channels
- assisted by a carrier molecule.
The unassisted diffusion of lipid-soluble or very small particles is called
Simple diffusion
Type of diffusion that is passive in movement of certain solutes across the membrane, but still needs to bind with a membrane carrier protein or by moving through a membrane channel. As with all types of diffusion, it is driven by kinetic energy, but the carriers and membranes are selective.
Facilitated diffusion
In simple diffusion, lipid-soluble substances diffuse directly through the lipid bilayer. What are such substances?
Oxygen
Carbon dioxide
Fat-soluble vitamins
In which the transported substance either (1) binds to protein carriers in membrane and is ferried across or (2) moves through water-filled protein channels.
Fascilitated diffusion
Diffusion of a SOLVENT, usually WATER, through a selectively permeable membrane. Water diffuses through membrane channels (aquaporins) or directly through the lipid portion of the membrane from a solution of high concentration to lower concentration to even out concentrations of solutes that cannot permeate the semipermeable membrane
Osmosis
The movement of molecules driven by kinetic energy down a concentration gradient.
Diffusion
All diffusion is driven by
Kinetic energy
The measure of the osmotic pressure of two solutions separated by a semi-permeable membrane
Tonicity
If a solution is hypotonic, the red blood cell will
Swell
If a solution is hypertonic, the red blood cell will
Shrink
The types of diffusion are
Diffusion
Facilitated diffusion
Osmosis
If a solution is hypotonic, the red blood cell will
Swell/Lyse
If a solution is hypertonic, the red blood cell will
Shrink/Crenate
Active Transport requires carrier proteins (solute pumps) which bind ____ and _____ with substance
specifically, reversibly
Active transport moves solutes ___ concentration gradient
Against
Primary active transport requires energy ____ from ATP hydrolysis
directly
Active Transport requires carrier proteins (solute pumps) which bind ____ and _____ with a substance
specifically, reversibly
Active transport moves solutes ___ concentration gradient and requires energy to do so.
Against
Type of transport that depends on a carrier protein and energy (solute pumping)
Active transport
What is an example of active transport?
Na + -K + pump (sodium potassium pump)
In secondary active transport, the energy of an ion gradient is produced by
A primary active transport process such as the sodium potassium pump
How is the energy used in secondary active transport?
To transport a substance passively.
What is another type of transport that requires that its energy be provided?
Vesicular transport
Type of vesicular transport which brings substances into the cell, typically protein coated vescicles
Endocytosis
Type of vesicular transport which brings substances that are large into the cell, this process is called
Phagocytosis
Type of vesicular transport which brings dissolved molecules into the cell
Pinocytosis (to drink)
Selective process in which engulfed molecules attach to receptors on the membrane before endocytosis occurs.
Receptor-mediated endocytosis
Active process which used SNAREs to anchor the vesicles to the plasma membrane and then ejects substances (hormones, wastes, secretions) from the cell.
Exocytosis
