Question

In: Biology

Describe the sequence of steps for an action potential of one neuronal cell leads to the...

Describe the sequence of steps for an action potential of one neuronal cell leads to the action potential in a postsynaptic cell.

Solutions

Expert Solution

A resting neuron is in polarised state, it means there is a charge difference across the membrane of a neuron. Positive charge is more outside and negative charge is more inside. This charge difference generates a membrane potential known as the resting membrane potential. The resting membrane potential of a neuron is -70mV. This charge difference is mainly generated by the sodium-potassium ATPase. Sodium-potassium ATPase pumps 3 Na+ ions outside and takes in 2 K+ ions. So, a resting neuron has more K+ ions inside and more Na+ ions outside.
Membrane of a neuron also has sodium and potassium voltage gated channels due to these channels depolarisation and repolarisation takes place. An action potential or a wave of depolarisation is generated when opening of voltage gated channels cause huge influx of Na+ ions. Voltage gated Na+ channels open when the membrane potential reaches threshold potential.  Influx of Na+ ions via voltage gated sodium channels first depolarises the membrane near the axon hillock and from the axon hillock wave of depolarisation moves towards the axon terminal. At the axon terminal neurotransmitters are stored in the synaptic vesicles. When the action potential reaches the axon terminals it opens the voltage gated calcium channels and causes influx of calcium ions. Calcium ions cause exocytosis of the neurotransmitter into the synaptic cleft. Released neurotransmitter then binds to the post-synaptic neuron and generates action potential.


Related Solutions

Compare and Contrast the Neuronal Action Potential vs Cardiac Action Potential. Focus on the steps of...
Compare and Contrast the Neuronal Action Potential vs Cardiac Action Potential. Focus on the steps of the both action potentials and identify the difference(s). What is the significance and involvement of Calcium ions in the cardiac action potentials? Why are Calcium ions not necessary in the neuronal action potentials, but are essential in the myocardial AP?
Compare and Contrast the Neuronal Action Potential vs Cardiac Action Potential. Focus on the STEPS (depolorization,...
Compare and Contrast the Neuronal Action Potential vs Cardiac Action Potential. Focus on the STEPS (depolorization, refractory period repolorization, Na/K pumps, resting membrane potential, ect...) of the both action potentials and identify the difference(s). What is the significance and involvement of Calcium ions in the cardiac action potentials? Why are Calcium ions not necessary in the neuronal action potentials, but are essential in the myocardial AP?
13. Describe the basic sequence of events that occurs as an action potential arrives at the...
13. Describe the basic sequence of events that occurs as an action potential arrives at the neuromuscular junction and is transmitted to the muscle cell and leads to a contraction. Explain at the end how relaxation of the muscle takes place (include what happens at the neuromuscular junction and in the muscle fiber. You may use some words multiple times. Fill in the blanks with a complete word or words (no abbreviations) of each step. 1. An action potential arrives...
Describe the steps in a chemical synapse from the arrival of an action potential at the...
Describe the steps in a chemical synapse from the arrival of an action potential at the pre-synaptic membrane to the formation of a graded potential on the post-synaptic membrane. Include as much biological detail as you can.
Describe the steps of an action potential and synapse. Include the role of myelin.
Describe the steps of an action potential and synapse. Include the role of myelin.
Describe in detail the action potential of an SA nodal cell of the heart. Be sure...
Describe in detail the action potential of an SA nodal cell of the heart. Be sure to names the phases, include the main types of membrane proteins involved, how they are opened, the movements of ions, and the changes in membrane potential. Explain how this type of action potential is different from that seen in a skeletal muscle cell and why the difference(s) are significant.
describe the process of the action potential in the nerve cell? what ions are involved and...
describe the process of the action potential in the nerve cell? what ions are involved and how are they involved?
Which statement with regards to neuronal membrane potential is CORRECT? A) The interior of a cell...
Which statement with regards to neuronal membrane potential is CORRECT? A) The interior of a cell has a positive baseline voltage. B) There is a higher concentration of potassium ions in the intracellular fluid. C) An action potential begins at a membrane potential of 0mV. D) Peripheral neurons have a different transmembrane potential than central neurons. E) The electrical potential inside a neuron is the same as outside.
Ganglionic cells are first cell to develop an action potential in the visual transduction. Describe the...
Ganglionic cells are first cell to develop an action potential in the visual transduction. Describe the effect of light in pigments inside rods, how light affects the polarization of photoreceptors, and how that affects bipolar cells and ganglionic cells.
Draw and label the action potential. Indicate steps 1-7 at each point of the Action Potential....
Draw and label the action potential. Indicate steps 1-7 at each point of the Action Potential. Then tell me what happens at each point. Tell me why it is important to know the steps of the Action Potential and how it works, and what it does in the body.
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT