PSB 2000 Exam 1 (Neurophysiology) | UPDATED Questions with 100% Verified Answers

PSB 2000 Exam 1 (Neurophysiology) | UPDATED
Questions with 100% Verified Answers
Q1: Ions that are most highly concentrated inside of the cell at rest
A: Negatively charged proteins (A-) and Positively charged Potassium ions (K+)


Q2: Ions that are most highly concentrated outside of the cell at
rest
A: Sodium (Na+) and Chlorine (Cl-)


Q3: How resting membrane potential is maintained
A: The semi permeable nature of the membrane (ions can't cross on own or move through
channels) and Sodium-potassium pump (3 Na+ out, 2 K+ in)


Q4: Concentration gradient
A: Force of diffusion. Particles move from areas of high concentration to areas of low
concentration


Q5: Electrical gradient
A: Force of electrostatic forces. Like charges repel each other, opposite charges are
attracted to each other


Q6: Voltage gated channel
A: open and close in response to changes in membrane potential. Located in the cell
membrane


Q7: Action potential step 1
A: Na+ channels open, Na+ begins to enter cell


Q8: Action potential step 2
A: K+ channels open, K+ begins to leave cell


Q9: Action potential step 3
A: Na+ channels become refractory, no more Na+ enters the cell


Q10: Action potential step 4
A: K+ continues to leave the cell, causes membrane potential to return to resting level


Q11: Action potential step 5
A: K+ channels close, Na+ channels reset