UNIT 3 AOS1 Flashcards
What are the 3 main roles of the Nervous System?
Reception
Processing
Response
Reception.
Receives sensory stimuli. Internal and external. eg heart rate.
Process
Making sense or interpretation.
Respond
Physical action. eg using skeletal muscle - internal muscle.
eg. sweat.
Central Nervous System.
- Brain
- Spinal cord ( Spinal Reflex )
Peripheral Nervous System.
Contains all of the neurons/nerves outside of the CNS. Carries information to the spinal cord, and then from the spinal cord to connect the brain with voluntary muscles, sensory receptors, and involuntary muscles.
Somatic.
Voluntary skeletal muscles.
Sensory and Motor neurons.
Sensory
Afferent, towards the CNS.
Motor
Efferent, away CNS.
Autonomic.
Involuntry.
Sympathetic and Parasympathetic.
Sympathetic.
Prepares the body for action, responding to a threat.
Flight or Fight.
eg. Dilated pupils, increased heart rate, bladder relaxes, digestion stops.
Parasympathetic
Homeostasis. A level of calm.
eg. Heart rate decreases, temperature decreases.
Fight or Flight
Response for survival when under threat.
Interneurons
Afferent and Efferent, in the CNS.
Effector.
Muscle - whatever is having the effect.
Receptor.
Detects the stimulus.
Spinal Reflex.
Involuntry, unconscious. Somatic.
Response to certain potentially damaging stimuli without the involvement of the brain. It is automatically reflected back from the spinal cord.
Dendrites
Receive messages from other cells - receptors, other neurons.
Receive information using receptor sites.
The information exits in the form of neurotransmitters which are chemicals.
Cell body (soma)
Converts the chemical neurotransmitter message to an electrical message known as an action potential.
Axon
Carries the action potential (electrical message).
Axon terminal
Receives electrical messages and releases stored neurotransmitter chemicals.
Types of neurochemicals
Neurotransmitters
Neuromodulators
Neurotransmitters
- used at a single synapse.
- ONE post-synaptic neuron responds.
Glutamate + GABA.
Neuromodulator
- at any multiple synapses.
- MANY post-synaptic neurons respond.
Dopamine + Serotonin.
Glutamate
Memory - Neurotransmitter (Excitatory)
Dopamine
Pleasure - Neuromodulator (Excitatory)
Serotonin
Mood - Neuromodulator (Inhibitory).
GABA
Calming - Neurotransmitter (Inhibitory)
Excitatory
Increased chance of action potential/release electrical impulse/fire.
Inhibitory
Decreased chance of action potential/release electrical impulse/fire.
Threshold
Excitatory: Once over the threshold, the post synaptic neuron has reached action potential.
Inhibitory: Decreases until resting.
Neurotransmitters’ effects on postsynaptic neuron….
Excitatory & Inhibitory.