[05] Biophysics of Nerve Conduction

Question 1

What is nerve conduction?

Answer 1

It is the process of nerves transmitting electrical impulses.

Question 2

Which cells are mainly involved in nerve conduction?

Answer 2

Neurons

Question 3

Define “Neuron”.

Answer 3

It’s a nerve cell that is the basic unit of the nervous system, transmitting information to other nerve cells, muscle, or gland cells.

Question 4

What is an “Action Potential”?

Answer 4

It’s the change in electrical potential that occurs between the inside and outside of a nerve or muscle fiber when stimulated, resulting in transmission of an impulse.

Question 5

How does an action potential travel along a neuron?

Answer 5

It travels along the neuron as a wave of depolarization caused by the flow of ions in and out of the neuron.

Question 6

What role does the “Axon” play in nerve conduction?

Answer 6

The axon conducts electrical impulses away from the neuron’s cell body.

Question 7

Define “Dendrite”.

Answer 7

Dendrites are branched extensions of a neuron that act to propagate the electrochemical stimulation received from other neurons to the cell body.

Question 8

What are “Synapses” in the context of nerve conduction?

Answer 8

Synapses are the junctions where neurons pass signals to other neurons, muscles, or glands.

Question 9

What is the function of “Neurotransmitters” in nerve conduction?

Answer 9

Neurotransmitters are chemical messengers that transmit signals across a synapse from one neuron to another ‘target’ neuron, muscle cell, or gland cell.

Question 10

Define “Resting Potential”.

Answer 10

It’s the electrical potential of a neuron or other excitable cell relative to its surroundings when not stimulated or involved in passage of an impulse.

Question 11

How does the “Sodium-Potassium Pump” contribute to nerve conduction?

Answer 11

It maintains the resting potential by pumping three sodium ions out of the neuron for every two potassium ions pumped in.

Question 12

What is “Depolarization”?

Answer 12

It’s a change in a cell’s membrane potential, making it more positive, or less negative. In neurons, it results from the flow of positively charged ions into the cell.

Question 13

What is “Hyperpolarization”?

Answer 13

It’s a change in a cell’s membrane potential that makes it more negative. It inhibits the generation of an action potential.

Question 14

What is “Refractory Period” in the context of nerve conduction?

Answer 14

It’s a period immediately following stimulation during which a nerve or muscle is unresponsive to further stimulation.

Question 15

What is the significance of the “Myelin Sheath” in nerve conduction?

Answer 15

The Myelin Sheath insulates the axon and increases the speed of nerve impulse transmission.

Question 16

What happens during “Repolarization”?

Answer 16

The cell’s membrane potential is restored to the negative value of the resting state after the depolarization of an action potential.

Question 17

How does “Saltatory Conduction” speed up nerve impulses?

Answer 17

In saltatory conduction, the nerve impulse jumps from one node of Ranvier to the next, skipping the myelinated sections of the axon, which speeds up the impulse.

Question 18

Define “Nodes of Ranvier”.

Answer 18

Nodes of Ranvier are small gaps in the insulating myelin sheath of a nerve cell where the nerve impulse is transmitted.

Question 19

What role does calcium play in neurotransmitter release?

Answer 19

When an action potential reaches the end of a neuron, it triggers the influx of calcium ions, which then triggers the release of neurotransmitters into the synapse.