Membrane Transport Mechanisms Flashcards
Define kinetic energy
energy that the body possesses as a result of motion (energy of motion)
define thermal energy
internal energy of an object that results from the kinetic energy of its atoms/molecule (kinetic energy of moving molecules)
Which transport mechanism requires energy other than kinetic energy
active transport
what do active transport and facilitated diffusion have in common?
the both use a carrier
what ion is most concentrated in the extracellular environment
sodium
The sodium potassium pump is an example of which of the following types of transport
primary active transport
the sodium glucose pump is an example of which of the following kinds of transport
secondary active transport
the sodium calcium pump is an example of which of the following kinds of transport
secondary active transport
glucose transporters employ which of the following kinds of transport
facilitated diffusion
define diffusion
random movement of molecules from high concentration to low concentration
define osmosis
movement of a solvent from a region of high concentration to a region of low concentration across a semipermeable membrane (semipermeable membrane is needed)
what does osmotic pressure depend on
the concentration of osmotically active particles (van’t Hoff’s law)
what types of transport are energy independent
diffusion
osmosis
facilitated diffusion
what is the difference between primary and secondary active transport
primary requires ATPases and secondary requires multiporters
what are ATPases
enzymes that split the phosphate of ATP and transfer it to another molecule (basically transferring energy) and effect transfer across the membrane (directly requires ATP)
what factors effect diffusion
proportional to concentration difference across membrane
membrane electric potential
pressure difference
what are some factors that increase permeability in diffusion
increased oil/water coefficient
decreased size of soluble
decreased membrane thickness
what is the function of the selectivity filter and how does it work
the selectivity filter is used in order to give preference to certain ions over others. it forms the most constricted part of the conduction pathway. it is a constriction of the channel ringed by negatively charged carbonyl oxygens
which type of neuron transmits an action potential the fastest
large diameter, myelinated
saltatory conduction is characteristic of what part of a typical neuron
axon
a selectivity filter with carbonyl oxygens is associated with which of the following kinds of ion channels
potassium
the resting potential for a typical neuron (such as a motor neuron) is best represented by what potential?
-90mV
