7. Describe the 7 steps of an action potential (with diagram). What happens to Na and
K channels at each step?
Give this one a try later!
1 depolarizing stimulus Na channel begin to open
2 reaching threshold -40mV - Na channels further open - action potential
will occur
3 rapid depolarization, massive Na influx through more open channels,
reaching Na equilibrium potential +50
4 Na channels inactivate - stop conducting sodium, even though the
membrane is depolarized
5 K channels open
6 K influx - membrane is repolarized back to negative potentials
7 back to rest, all channels are closed
__ transporters can be either active or passive, but ion channels are always active
, Give this one a try later!
false, ion channels are always passive
16. Cystic fibrosis involves a defect in the mechanism that puts a transmembrane into
the plasma membrane. Describe the path of transmembrane proteins from synthesis
to destination. What goes wrong with the cystic fibrosis mutated protein?
Give this one a try later!
16. Proteins destined for plasma membrane (or secretion) will be
synthesized into the ER upon recognition of N terminal ER sequence.
They will be folded correctly in the ER by chaperones, and modified with
SS bonds and glycosylation (as needed)
Then transported to the golgi for further modifications and processing
Proteins that are not folded correctly will retain in the ER and eventually
moved to the cytosol and degraded.
Cystic fibrosis mutation leads to a slightly misfolded protein - activates the
ER response, causing it to be retained in the ER and degraded. The protein
never reaches the surface of the cell, where it could have functioned as a
channel
What types of information can be conducted between neurons?
Give this one a try later!
Information can be excitatory or inhibitory
What will happen if Na channels did not open?
K channels at each step?
Give this one a try later!
1 depolarizing stimulus Na channel begin to open
2 reaching threshold -40mV - Na channels further open - action potential
will occur
3 rapid depolarization, massive Na influx through more open channels,
reaching Na equilibrium potential +50
4 Na channels inactivate - stop conducting sodium, even though the
membrane is depolarized
5 K channels open
6 K influx - membrane is repolarized back to negative potentials
7 back to rest, all channels are closed
__ transporters can be either active or passive, but ion channels are always active
, Give this one a try later!
false, ion channels are always passive
16. Cystic fibrosis involves a defect in the mechanism that puts a transmembrane into
the plasma membrane. Describe the path of transmembrane proteins from synthesis
to destination. What goes wrong with the cystic fibrosis mutated protein?
Give this one a try later!
16. Proteins destined for plasma membrane (or secretion) will be
synthesized into the ER upon recognition of N terminal ER sequence.
They will be folded correctly in the ER by chaperones, and modified with
SS bonds and glycosylation (as needed)
Then transported to the golgi for further modifications and processing
Proteins that are not folded correctly will retain in the ER and eventually
moved to the cytosol and degraded.
Cystic fibrosis mutation leads to a slightly misfolded protein - activates the
ER response, causing it to be retained in the ER and degraded. The protein
never reaches the surface of the cell, where it could have functioned as a
channel
What types of information can be conducted between neurons?
Give this one a try later!
Information can be excitatory or inhibitory
What will happen if Na channels did not open?
