Question 1
Inhibitory postsynaptic potentials (IPSPs)
◦ increase membrane permeability to sodium ions.
◦ result in depolarizations.
◦ result in hyperpolarizations.
◦ decrease potassium ion exit from cells.
◦ decrease calcium ion exit from cells.
Question 2
When two or more graded potentials arrive at the trigger zone, which of the following could happen?
◦ Two inhibitory stimuli may be additive, resulting in lower excitability.
◦ An excitatory and inhibitory signal can cancel each other out and two excitatory stimuli may be additive, and summation could occur.
◦ An excitatory and inhibitory signal can cancel each other out.
◦ Two excitatory stimuli may be additive, and summation could occur.
◦ An excitatory and inhibitory signal can cancel each other out; two excitatory stimuli may be additive, and summation could occur; and two inhibitory stimuli may be additive, resulting in lower excitability.
Distributions of two barnacle species within the intertidal zone
Common trigger point locations, anterior and posterior.
Finger pressure to a trigger point.
The Danger Zone
Action Potentials: Stimulus Strength
Comparison of Graded & Action Potentials