All Flashcards
Define 'nervous system'.
The body's communication network using electrical and chemical signals.
What is the 'Central Nervous System (CNS)'?
The brain and spinal cord; the main processing center.
Define 'Peripheral Nervous System (PNS)'.
Connects the CNS to the rest of the body.
What is the 'Somatic Nervous System'?
Controls voluntary movements of skeletal muscles.
Define 'Autonomic Nervous System'.
Controls automatic functions of internal organs.
What is the 'Sympathetic Nervous System'?
The 'fight or flight' system; prepares the body for action.
Define 'Parasympathetic Nervous System'.
The 'rest and digest' system; calms the body down.
What are 'Neurons'?
Basic building blocks of the nervous system; transmit information.
Define 'Action Potential'.
Electrical signal that travels down the axon of a neuron.
What are 'Neurotransmitters'?
Chemical messengers that travel across the synapse.
Define 'Synapse'.
The gap between two neurons where neurotransmitters are released.
What is 'Depolarization'?
The process of the neuron becoming more positive, allowing the action potential to travel.
Describe the steps of an action potential.
- Neuron is at resting potential. 2. Depolarization occurs. 3. Threshold is reached. 4. Action potential is triggered. 5. Repolarization occurs. 6. Resting potential is restored.
What is the process of neurotransmission?
- Synthesis of neurotransmitters. 2. Release into the synapse. 3. Binding to receptors on the postsynaptic neuron. 4. Signal propagation. 5. Removal of neurotransmitters from the synapse.
Describe the 'fight or flight' response.
- Threat perceived. 2. Sympathetic nervous system activated. 3. Heart rate increases. 4. Breathing quickens. 5. Adrenaline released. 6. Body prepares for action.
What is the process of the 'rest and digest' response?
- Threat subsides. 2. Parasympathetic nervous system activated. 3. Heart rate decreases. 4. Breathing slows. 5. Body returns to a calm state.
Describe the steps of a reflex arc.
- Sensory receptor detects stimulus. 2. Sensory neuron transmits signal to spinal cord. 3. Interneuron processes signal. 4. Motor neuron transmits signal to muscle. 5. Muscle contracts.
What is the effect of sympathetic nervous system activation?
Increased heart rate, faster breathing, and heightened alertness.
What is the effect of parasympathetic nervous system activation?
Decreased heart rate, slower breathing, and relaxation.
What is the effect of damage to the spinal cord?
Loss of motor control and sensation below the injury site.
What is the effect of neurotransmitter imbalance?
Can lead to various psychological disorders, such as depression or anxiety.
What is the effect of a strong stimulus on a neuron?
Triggers an action potential if the threshold is reached.
What is the effect of blocking neurotransmitter reuptake?
Increased concentration of the neurotransmitter in the synapse, prolonging its effects.
What is the effect of myelin sheath damage?
Slower or disrupted nerve impulse transmission.
What is the effect of a neuron not reaching its threshold?
No action potential is generated; the neuron does not fire.
What is the effect of an inhibitory neurotransmitter?
Decreases the likelihood of the postsynaptic neuron firing.
What is the effect of an excitatory neurotransmitter?
Increases the likelihood of the postsynaptic neuron firing.