Podcast
Questions and Answers
What is the function of afferent nerve impulses?
What role do synaptic vesicles play in neurotransmission?
What does synaptic transmission involve?
Which event occurs immediately after neurotransmitters are released into the synaptic cleft?
Signup and view all the answers
How do local anaesthetics block nerve transmission?
Signup and view all the answers
What condition results from excessive nerve impulses?
Signup and view all the answers
What happens when the herpes simplex virus reactivates?
Signup and view all the answers
How are neurotransmitters inactivated after their action?
Signup and view all the answers
Study Notes
Nerve Impulses
- Nerve impulses are initiated by stimulation of sensory nerve endings or by the passage of an impulse from another nerve.
- Afferent (sensory) impulses travel TO the brain and CNS.
- Efferent (motor) impulses travel FROM the brain and CNS.
- Nerve impulses travel down the neurone.
Synaptic Transmission
- Synapse: the point at which a nerve impulse jumps from one nerve to another.
- There are approximately 1000 trillion synapses in the brain.
- Synaptic knobs contain synaptic vesicles which store neurotransmitters.
- Neurotransmitters are released into the synaptic cleft.
Neurotransmitter Journey
- Synthesized by nerve cell bodies.
- Actively transported along the axons.
- Stored in synaptic vesicles.
- Released by exocytosis in response to the action potential.
- Diffuse across the synaptic cleft.
- Act on specific receptor sites on the post synaptic membrane.
- Action is short-lived.
- Inactivated by enzymes or taken back into the synaptic knob after action.
Local Anaesthetics
- Block nerve transmission to pain centers by inhibiting sodium channels in the cell membrane of nerve cells.
- This action obstructs the movement of nerve impulses near the site of injection, but awareness and sense perception in other areas are not affected.
Neuralgia
- Excessive nerve impulses can result in neuralgia.
- Trigeminal neuralgia is the most common type.
- Herpes simplex virus lies dormant in the trigeminal ganglion.
- When reactivated, the herpes simplex virus travels down the trigeminal nerve emerging on the lip and causing a cold sore.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
