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Resting membrane potential did not change with decreased extracellular Na+  because the membrane has [x] Na+ leak channels than K+ leak channels and therefore changing Na+ concentrations has [y] effect on membrane potential.

Activity 6: Multiple action potentials were generated in response to a 500 msec duration stimulus because the [a] stimulus results in stimulation during the [b]. The stimulus is [c] which is required for an action potential to be generated during the [d] phase of the action potential.

In Activity 2, which of the following responded to a chemical stimulus?  Use your data chart to answer.

Pain-sensitive neurons conduct action potentials from the skin or teeth to sites in the brain involved in pain perception. To most effectively prevent the perception of pain a dentist would inject [a] near the [b] to [c] the generation of action potentials that would send a signal to the brain.

In Activity 5, when the interval between the stimuli decreases, _______.

What type of sensory receptor would have responded to the light stimulus?

Activity 7:  The squid utilizes a very large-diameter, unmyelinated axon to execute a rapid escape response when it perceives danger.  Due to the large-diameter, the velocity of the action potential is [a] that of a smaller diameter axon, because the larger fiber has less internal resistance to local current.  This allows a greater flow of ions in a set time bringing adjacent areas of the membrane to threshold, allowing a [b] conduction velocity of action potentials and a rapid escape response. This helps compensate for the lack of myelin.

An example of a stimulus modality as tested in this experiment (Activity 2) is ________.  Use the exact terminology from the Lab Manual and Activity 2 Data Chart.  Use one word and correct spelling is needed for credit.  

Activity 2: Graded potentials [x].

Establishing the ion gradients (sodium and potassium) responsible for the resting membrane potential requires energy through the use of the _______.