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Flashcards in EXCITABLE TISSUE Deck (18):
1

potassium

- cation positive charges leaves negative
- concentration gradient forced potassium out of the cell
- the electrical gradient keeps potassium in (NaKATPase pump)
- efflux out of the cell is the normal conduction of K
- passive
- not energy dependent no ATP needed
- resting membrane potential is very sensitive to changes in the EXTRACELLULAR K+
- gives CARDIAC problems

2

Na K ATPase

- needs energy

3

membrane conductance

- ungated channels
- voltage gated channels
- ligand gated channels

4

ungated channels

- concentration

5

voltage gated channels

- positive (+) and negative (-) charges
- Cl-
- Na K +

6

ligand gated

- protein transporter channel

7

cell is

- NEGATIVE
- sodium and potassium is POSITIVE

8

-70 mV

- keeps the potassium IN

9

membrane potential

- -70 and - 90mV

10

resting membrane potential

- INSIDE THE CELL -90mV more negative hyper polarization
low Cl-
high K +
low Na +
- OUTSIDE THE CELL
high Cl-
low K+
high Na+

11

depolarization

- normally intracellular charge is NEGATIVE
- rapid influx of sodium INTO the cell
- fast
- increase K extracellularly influx
- cell BECOMES more POSITIVE

12

repolarization

- based on the pump

13

hyperpolarization

- potassium LEAVING the cell
- making THE CELL more NEGATIVE -70mV

14

rhabdomyolysis
tumor lysis
hemolysis

- K levels in the blood is INCREASED
- INFLUX of the cell due to sudden increase in K
- depolarized the cell
- causing arrhythmia

15

seizure most common cause of death

- hyperkalemia depolarizing the cell then death occurs

16

sodium

- is higher extracellularly
- not involved in resting membrane potential
- CNS problems

17

pumping Na+ out of the cell

- K pump into the cell (active, energy)
- K diffusion

18

POTASSIUM brings the cell

- into EQUILIBRIUM