Nerve Impulse Conduction
Information is transmitted both quickly and accurately by electrical means through
When your finger gets accidently caught at the door, the pain message is sent to your brain through:
The conduction of the nerve impulses through the neurons is similar to the conduction of electricity through a wire.
The membrane of an unstimulated neuron is unpolarised.
- First positive, then negative and continue to be negative
- First negative, then positive and continue to be positive
- First positive, then negative and again back to positive
- First negative, then positive and again back to negative
Which one of the following describes saltatory conduction ?
Faster than conduction on an unmyelinated fiber
Occurs only if nodes of Ranvier are lacking
Occurs only if the myelin sheath is continuous
Slower than conduction on an unmyelinated fiber
Stimulation of a neuron in resting state causes _____.
No change in the state of rest
- K+ ions from intracellular fluid to extracellular fluid
- Na+ ions from extracellular fluid to intracellular fluid
- K+ ions from extracellular fluid to intracellular fluid
- Na+ ions from intracellular fluid to extracellular fluid
- Fluid outside the axon has a high concentration of Na+ and low concentration of K+ in a resting neuron.
- Ionic gradients are maintained by Na - K pumps across the resting membrane which transport 3Na+ ions outwards for 2K+ ions into the cell.
- A neuron is polarised only when the outer surface of the axonal membrane possess a negative charge and its inner surface is positively charged.
- Resting potential is the electrical potential difference across the resting membrane.
- In a resting neuron, the axonal membrane is more permeable to K+ ions and nearly impermeable to Na+ions.
- First negative then positive and again back to negative
- First positive then negative and continue to be negative
- First negative then positive and continue to be positive
- First positive then negative and again back to positive