lecture 17 - functional info flow Flashcards
What are the two types of information transmitted in the nervous system?
Somatic and Autonomic
What is somatic information in the nervous system?
Action we are aware of/can control, e.g. voluntary muscle control (efferent), sensory information (afferent)
What is autonomic information in the nervous system?
Information and control we are not aware of and have no control over. e.g. involuntary muscle control (efferent), sensory info we are unaware of (afferent)
How many neurons are found between the brain and effector in the somatic efferent division?
2
What are the neurons found in the Somatic efferent division?
Upper and lower motor neuron
Where are the components of the upper motor neuron in the somatic efferent division?
CNS - Cell body in brain, axon in spinal cord
Where are the components of the lower motor neuron in the somatic efferent division?
PNS - cell body in spinal cord, axon in spinal nerve, synapse on effector in PNS
Are the axons of the somatic efferent division of the nervous system myelinated or unmyelinated?
Myelinated
What is the neurotransmitter used by the spinal nerve at a neuromuscular junction in the somatic efferent division?
Acetylcholine
What are the two divisions of the autonomic nervous system?
Sympathetic and parasympathetic.
What are the common effectors of the autonomic nervous system (4)?
Smooth and cardiac muscle, glands, adipose tissue
How many neurons are there between the brain and the effector in the autonomic efferent division of the CNS?
3
What is the location of neuron 1 in the autonomic efferent division of the nervous system?
Cell body in brain, axon in brain/spinal cord.
What is the location of neuron 2 in the autonomic efferent division of the nervous system?
Cell body in brain/spinal cord, axon in PNS
What is the location of neuron 3 in the autonomic efferent division of the nervous system?
Cell body and axon in PNS, with synapse at effector
Is neuron 2 in the autonomic efferent division of the nervous system myelinated or unmyelinated?
Myelinated
Is neuron 3 in the autonomic efferent division of the nervous system myelinated or unmyelinated?
Unmyelinated
What is the function of the sympathetic autonomic nervous system?
Prepare the body for acute/stress responses - e.g. ‘fight or flight’
What are examples of body functions controlled by the sympathetic autonomic nervous system?
Heart rate, vasoconstriction, gastric motility, salivation, pupil size, sweating
What is the neurotransmitter used at the synapse between neurons 2 and 3 in the autonomic efferent division?
Acetylcholine (ACh)
What are the neurotransmitters used at the synapse between neuron 3 and the effector in the autonomic efferent division?
Acetylcholine/ACh (parasympathetic), Norepinephrine/NE (sympathetic)
What neurotransmitter is used at the synapse of neuron 3 and the effector in the sympathetic autonomic efferent system?
Norepinephrine (NE)
What neurotransmitter is used at the synapse of neuron 3 and the effector in the parasympathetic autonomic efferent system?
Acetylcholine (ACh)
What is the location of neuron 2 in the sympathetic autonomic efferent division?
Cell body - ‘pre ganglionic’ thoracolubular levels of spinal cord (CNS). Axon - Terminals are in sympathetic chain ganglion
What is the location of neuron 3 in the sympathetic autonomic efferent division?
Cell body - ‘post ganglionic’, in sympathetic chain ganglion. Axon - In PNS. Output - peripheral effector
What are the relative sizes of neuron 2 and 3 in the sympathetic efferent autonomic nervous system?
Neuron 2 is short, Neuron 3 is long (extends from sympathetic chain ganglion all the way to the effector)
What part of the nervous system are the sympathetic chain ganglia associated with?
Sympathetic autonomic efferent
What is the location and basic structure of the sympathetic chain ganglia?
Found in 21 to 23 pairs on either side of the vertebral column. Cell bodies of pre ganglionic neurons found within thoracolumbar region (lumbar and thoracic nerves) with axons connecting to the chain ganglia where the post ganglionic neuron cell bodies are located.
What is the function of the parasympathetic nervous system?
Prepare the body for restful situations.
What are some examples of actions of the parasympathetic nervous system?
Decreased: heart rate gastric motility, pupil size, salivation
What is the neurotransmitter used at the synapse between neuron 2 and 3 in the parasympathetic nervous system?
Acetylcholine (ACh)
What neurotransmitter is used at the synapse of neuron 3 and the effector in the parasympathetic autonomic efferent system?
Acetylcholine
What is the location of neuron 2 in the parasympathetic autonomic efferent system?
Cell bodies - cranial (brain stem) and sacral (spinal cord) levels. Axon - parasympathetic ganglia (located in/near the effector)
What is the location of neuron 3 in the parasympathetic nervous system?
Cell bodies - in parasympathetic ganglia near effector organs. Axon - Short and connects straight to effector
What are the relative sizes of neurons 2 and 3 (their axons) in the parasympathetic nervous system?
Neuron 2 is long, Neuron 3 is short
In sympathetic efferent divisions, are the neuron axons myelinated or unmyelinated?
Neuron 2 myelinated, Neuron 3 unmyelinated
In parasympathetic efferent divisions, are the neuron axons myelinated or unmyelinated?
Neuron 2 myelinated, Neuron 3 unmyelinated
What is the alternative term for norepinephrine (NE)?
Noradrenaline
In terms of the parasympathetic/sympathetic nervous system, which neurons are pre ganglionic and which are post ganglionic?
Neuron 2 is preganglionic, Neuron 3 is postganglionic
