More physio Before Exam

Question 1

Threshold stimulus

Answer 1

Stimulus will bring membrane to threshold, thus AP will occurr

Question 2

Subthreshold stimulus

Answer 2

Transiently depolarizes the membrane, but not enough to bring membrane to threshold
No action potential occurs

Question 3

Suprathreshold stimulus

Answer 3

An ap of same MAGNITUDE and DURATION would occur as threshold stimilus

Question 4

Accommodation

Answer 4

Ability to adjust strength of lens so both far and near sources can be focused on the retina

Question 5

Regeneration of peripheral nerve fibers

Answer 5

1) Can occur if soma and neurilemmal tube is intact
2) stranded end of axon and myelin sheath degenerate
3) healthy axon stub puts our several sprouts
4) tube guides lucky sprout back to its original destination