An action potential is an “all or none” event.  What is meant by the phrase?  Use the data in your chart to support your explanation.  Be specific and be brief. 

The electrochemical gradient is a combination of an ion’s concentration gradient and ____.

If a graded receptor potential made the resting membrane potential of the axon more negative (for example from -70 mV to -74 mV), one would expect:

Activity 3:  The minimum voltage that is required to generate an action potential is called the _______.

How is axon diameter usually related to action potential conduction velocity?

Botulinum blocks release from axon terminals and is used for cosmetic purposes because it muscle and the appearance of wrinkles. Note: this is a question that addresses the application of some of the concepts you have been studying and you may have to research the topic.

Activity 8:  When stimulus intensity increases, 

Which of the following is true of the response of a sensory neuron to the appropriate sensory stimulus?

In Activity 2, which of the following was able to detect pressure?

Activity 1:  The resting membrane potential became less negative (-70 mV to – 40 mV) with increased extracellulkar K+ because K+ diffused out of the cell leaving  K+  inside the cell.   The following drawing may be helpful in evaluating Questions 1 and 2.