Understanding Neurons and Nerve Impulses

What is the primary function of neurons within the nervous system?

• To produce hormones

• To carry electrical impulses

• To store energy

• To digest nutrients

Which component of a neuron is responsible for converting chemical signals into electrical signals?

• Axon

• Soma

• Dendrites

• Myelin sheath

What is the resting potential of a typical neuron?

• +30 mV

• 0 mV

• -70 mV

• -30 mV

What process occurs when sodium channels open and sodium ions enter the neuron?

• Repolarisation

• Depolarisation

• Hyperpolarisation

• Resting potential

What is the role of the myelin sheath in neurons?

• To store neurotransmitters

• To insulate the axon and increase conduction speed

• To produce electrical impulses

• To generate action potentials

Which ions are exchanged by the sodium-potassium pump to establish a resting potential?

• Calcium and chloride

• Sodium and calcium

• Sodium and potassium

• Potassium and chloride

What is the charge difference across the membrane when a neuron is firing?

• -70 mV

• 0 mV

• +30 mV

• -30 mV

What is the refractory period in a neuron?

• The time when a neuron is actively firing

• The time when a neuron cannot fire again until the original ion distribution is restored

• The time when neurotransmitters are released

• The time when the neuron is at resting potential

What triggers the release of neurotransmitters from the presynaptic membrane?

• Opening of sodium channels

• Opening of potassium channels

• Opening of voltage-gated calcium channels

• Opening of chloride channels

What is the function of synapses in the nervous system?

• To store electrical impulses

• To act as junctions between neurons and effector cells

• To generate action potentials

• To insulate axons