In this phase, ALL voltage-gated Na+ channels are in the process of re-setting and cannot be opened rising phase falling phase absolute refractory period relative refractory period

Place the following events in chronological order from 1-8: Nat enters the cell, and depolarization occurs to approximately +30 mV. The voltage across the cell membrane is -70 mV, the resting membrane potential. Upon reaching the peak of the action potential, the VG Nat channels are inactivated by the closing of their inactivation gate and the activation gate of each VG K channel opens. VG K channels close by the closing of their activation gate, and the resting membrane potential is gradually restored. An excitatory post-synaptic potential depolarizes the membrane to threshold and the activation gate of VG Nat channels open. Upon returning to the resting membrane potential, VG Na channels are reset by opening of the inactivation gate and the closing of the activation gate. VG K+ channels are slow to close, resulting in an excess of K* efflux and hyperpolarization. Depolarization occurs as K+ flows out of the cell.

You have a photoreceptor cell in a dish. You are recording its membrane potential while flashing different intensities of light. Which of the following would you observe? Group of answer choices The cell hyperpolarizes, with brighter light causing more hyperpolarization than dimmer lights The cell depolarizes, with brighter light causing more depolarization than dimmer lights If the light is bright enough to reach threshold, it will fire an action potential No change in membrane potential will be observed

"After an action potential has just passed through the axon hillock, the voltage-gated Na+ channels there won t open for a period of time. However, if the stimulus is strong enough, another action potential can be triggered even during this resting time. This refers to"     refractory resting period     intermediate resting period     relative refractory period     absolute refractory period

Saltatory conduction occurs on?     Dendrites     Cell bodies     Unmyelinated axons     Myelinated axons     None of the above     All of the above

A neuron has a resting membrane potential of -70 milivolts (mV) and a threshold value of -55 mV. Three synapses on the body of this neuron receive the impulses listed below. hyperpolarisation by 5 mV • depolarisation by 15 mV • depolarisation by 10 mV ENTER THE MEMBRANE POTENTIAL AS A NUMBER WITH + OR - IN FRONT OF IT. The final membrane potential will be mV and this cause an action potential becasue it is v than the

Action potentials are produced by voltage-gated channels True False

during the absolute refractory period k+ channels are open while na+ channels are   1. activated 2.inactivated 3.deactivated

Continuos propagation of action potentials occurs in myelinated axons and is faster than conduction in unmyelinated axons.   True False

Summarize the steps in generating an action potential as a flowchart. You can make your flowchart on paper and take a picture of it, or make it electronically. Be sure you’ve included: the location in the neuron and components of the neuron involved, the types of cellular transport and ions involved, how action potentials can be stimulated and inhibited. you can get the information from this: https://youtu.be/HYLyhXRp298