Multiple Choice
What happens when the neuron reaches threshold (-55 mV)?
11. Nervous Tissue and Nervous System
Action Potentials
Back11. Nervous Tissue and Nervous System
Action Potentials
- Multiple Choice
Casey is taking a new medication that blocks potassium channels. What stage of an action potential would be MOST affected by this drug?
- Multiple Choice
When an action potential is at its peak, the electrical gradient forces potassium ____________.
- Multiple ChoiceWhich of the following electrical events occurs when a certain threshold is reached?
- Multiple ChoiceWhich of the following is characteristic of an action potential?
- Multiple ChoiceAn action potential is a phenomenon that either happens completely or doesn't happen at all.
- Multiple ChoiceWhich part of the action potential occurs when the voltage-gated Na+ channels are inactivating and voltage-gated K+ channels open?
- Multiple ChoiceThe CNS can discriminate between strong and weak stimuli as strong stimuli __________.
- Multiple ChoiceDuring which phase of an action potential are voltage-gated K+ channels open, while voltage-gated Na+ channels are closed?
- Open QuestionThe anatomical region of a multipolar neuron where the AP is initiated is thea. soma,b. dendrites,c. axon's initial segment,d. axon terminals.
- Open QuestionWhat is the polarized membrane state? How is it maintained? (Note the relative roles of both passive and active mechanisms.)
- Open QuestionDescribe the events that must occur to generate an AP. Relate the sequence of changes in permeability to changes in the ion channels, and explain why the AP is an all-or-none phenomenon.
- Open QuestionWhen admitted to the emergency room, Sean was holding his right hand, which had a deep puncture hole in its palm. He explained that he had fallen on a nail while exploring a barn. Sean was given an antitetanus shot to prevent neural complications. Tetanus bacteria fester in deep, dark wounds, but how do their toxins travel in neural tissue?
- Open QuestionRochelle developed multiple sclerosis when she was 27. After eight years she had lost a good portion of her ability to control her skeletal muscles. How did this happen?
- Open Question
Describe the three components of the neuromuscular junction.