Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
28 Cards in this Set
- Front
- Back
Voltage gated Na+ channels are sensitive to changes in extracellular concentration of _______ |
Ca++ |
|
Action potentials are constant in ________ |
Magnitude |
|
Another stimulus cannot cause another action potential during the absolute refractory period because... |
The voltage-gated sodium inactivation gate is closed |
|
This allows the action potential to propagate in an one-way direction |
Absolute refractory period |
|
After an action potential, a second action potential cannot occur until |
most of the sodium activation gates are shut |
|
The cell is permeable to Na+ again once |
repolarization is complete |
|
Increased K+ ions in extracellular fluid will cause |
depolarization |
|
During depolarization, what are the Na+ inactivation gate and activation gate doing? |
Activation and inactivation gates are both open |
|
When does the absolute refractory period end? |
When the inactivation gates of voltage-gated Na+ channels reopen |
|
If a cell has never had a Na+ K+ ATP-ase pump, where would it be located on an action potential graph? |
0 mV |
|
Action potentials happen with which kind(s) of channel(s)? |
ligand-gated and voltage-gated ion channels |
|
A new action potential is possible in the repolarization phase if... |
the repolarization potential value is lower than threshold |
|
During the course of an action potential, the membrane potential changes from positive to negative to positive, relative to the outside or inside of the cell? |
the outside |
|
How does reduced extracellular concentration of Na+ affect the magnitude of an action potential? |
The magnitude is decreased |
|
Which ion has the greatest influence on RMP? |
K+ |
|
what would happen if the extracellular concentration of K+ were decreased? |
Hyperpolarization |
|
The resting membrane potential is established mainly due to |
K+ leak channels |
|
At RMP, what would happen to the plasma membrane if Cl- flowed into the cell? |
Hyperpolarization |
|
Which organelle generates ATP? |
Mitochondrion |
|
what buds off the Golgi Apparatus? |
Lysosomes |
|
Functions of cytoskeleton |
maintains cell shape, resists deformation, transport and migratory movement, cell signaling, endocytosis & exocytosis, and cell division |
|
Basic structure of cell |
Plasma membrane Cytoplasm containing organelles Nucleus |
|
Factors that affect rate of diffusion |
concentration gradient temperature size of molecule viscosity of medium membrane permeability surface area distance |
|
osmolarity and tonicity of 0.9% saline solution |
isosmotic and isotonic |
|
osmolarity and tonicity of 5% dextrose solution |
Isosmotic and hypotonic |
|
osmolarity and tonicity of 5% dextrose + 0.9% saline solution |
hyperosmotic and isotonic |
|
osmolarity and tonicity of 0.45% saline |
hyposmotic and hypotonic |
|
osmolarity and tonicity of 5% dextrose + 0.45% saline solution |
hyperosmotic and hypotonic |