Neuro 2 Flashcards
Somatic definition and two types
- the stuff we are aware of, have control over
Voluntary muscle control: SOMATIC AFFERENT (motor)
Sensory information we are aware of: SOMATIC AFFERENT (sensory)
Autonomic definition and two types
- the stuff we are not aware of, have no control over
Involuntary muscle control: AUTONOMIC EFFERENT (motor). -heart beat
Sensory information that er don’t know about: AUTONOMIC AFFERENT (sensory) - blood pressure
Somatic efferent division
Two neurons between brain and effector:
- Upper motor neuron
- cell body in brain
- axon in spinal cord - Lower motor neuron
- cell body in spinal cord
- axon in spinal nerve
Effectors (things the nerves go to and control) = skeletal muscle fibres
Somatic efferent: anatomical organisation
- Upper motor neuron - cell body in Brian, axon in spinal cord CNS
- axon is myelinated - Lower motor neuron - cell body in spinal cord (CNS), axon in spinal nerve (PNS)
- axon in myelinated
Somatic efferent: communication with effector cells
AP travels through Lower myelinated motor neuron 2’s cell body in CNS and down the axon in the PNS - PRE-SYNAPTIC CELL
Acetyl Choline is realised (chemical) at the neuro mascular junction triggering the effector POST-SYNAPTIC CELL
somatic efferent division
- voluntary movement
- two neurons between brain + effector
1. UPPER motor neuron
2. LOWER motor neuron - axons myelinated
- neurotransmitter = Acetylcholine
- effector = skeletal muscle
Autonomic Efferent Nervous System kind of control?
- involuntary control
Two divisions of the autonomic efferent nervous system
- smooth muscle
- cardiac muscle
- glands
- adipose
- tissue
Three neurons between brian and effector
Neuron #1: (less focus in the exam)
- cell body in brain
- axon in PNS
Neuron #2:
- cell body in brain or spinal cord (CNS)
- axon in PNS
Neuron #3:
- cell body in PNS
- Axon in PNS
Autonomic nervous system: synaptic neurotransmitters: NEURON TWO
- Cell body in CNS
- Axon extends in PNS
- myelinated
- synapse in autonomic ganglion
- pre-ganglion if neuron
- neurotransmitter = acetylcholine
Autonomic nervous system: synaptic neurotransmitters : NEURON THREE
- cell body in PNS, autonomic ganglion
- axon extends in PNS, to effector organ
- unmyelinated
- synapse on effector organ
- post ganglionic neuron
- neurotransmitter = ACh or norepinephrine
Subdivisions of the autonomic nervous system: SYMPATHETIC
- prepares the body for acute/stress responses
- ‘fight of slight’ system
- norepinephrine
Effects include:
- increased heart rate
- constricting blood vessels to skin and viscera (increasing blood flow to muscles)
- decrease gastric motility
- decrease salivation
- increase pupil size
- increase sweating
Subdivisions of the autonomic nervous system: PARASYMPATHETIC
- Prepares the body for restful situations:
- “rest and digest” system
Effects include
- decreased heart rate
- increased gastric motility
- decreased pupil size
- increased salivation
Structural differences between sympathetic and parasympathetic nervous system
Sympathetc:
- short axon - neuron #2 - pre-ganglionic
- sympathetic ganglion - close to CNS
- long axon - neuron #3 - post-ganglionic
Parasympathetic:
- long axon - neuron #2 - pre ganglionic
- prarsmypathtic ganglion - distant from CNS
- short axon - neuron #2 - post ganglionic
Pre ganglionic neuron - exit from CNS and position of ganglia
- cell body in thoracolumbar levels of spinal card (CNS)
- axon is short
- terminals and synapse in sympathetic ganglion
Post ganglionic neuron - exit from CNS and position of ganglia
- cell body in sympathetic ganglion
- axon is long
Sympathetic chain ganglia
- on either dive of the vertebral column
- 21- 23 pairs
- place where preganglionic (neuron #2) synapse
- onto postganglionic (neuron #3) input zone
Structure of sympathetic chain ganglia
- Post ganlionic cell bodies in ganglion
- Long axons entend into body
- Unmyelinated
Sympathetic ganglion close to CNS
Parasympathetic nervous system: exit from CNS and position of ganglia:
Preganglionic neuron:
- cell bodies in cranial (brain stem) and sacral (spinal cord) levels
- axon is long
- axon terminals synapse in parasympathetic ganglia (in or near the effector)
Postganglionic neuron:
- cell body in parasympathetic ganglia in or near effector organs
- axon is short
