Functional Informational Flow

• Types of information transmitted in the nervous system are somatic and autonomic.
• Somatic information are the stuff we are aware of and have voluntary muscle control. Voluntary control is efferent (motor), and the sensory information we are aware of is afferent (sensory).
• Autonomic is the stuff we are not aware of and involuntary control over. Involuntary control is efferent and the sensory information we don't know about is afferent.
• Afferent sensory division is responsible for receiving sensory input from external and internal environment.
• Efferent motor division is responsible fro sending motor commands from CNS to muscles and glands.
• Anatomical organisation of somatic efferent division of nervous system:

  A) Upper

  B) Lower

  C) brain

  D) spinal cord

  E) spinal cord

  F) spinal nerve

  G) effectors

  H) skeletal muscle fibres

  
• The axon in the spinal cord is myelinated in the upper motor neuron and lower motor neuron.
• Axon myelination

  A) CNS

  B) PNS

  C) brain

  D) spinal cord

  E) synapse

  F) spinal nerves

  G) synapse

  H) effector

  
• The upper motor myelination increases speed and efficiency of the nerve impulse.
• The lower motor neuron myelination allows for efficient transmission of nerve impulses to muscles.
• more label

  A) ACh

  B) ACh

  C) Synaptic cleft

  D) Acetylcholine

  
• 1. Action potential generation is in the lower motor neuron. This is initiated by signals received from upper motor neurons.
• 2) Propogation of Action potential is when generated action potentials travel along the axon of the lower motor neuron. The axon is myelinated into rapid transmission.
• 3) Arrival at neuromuscular junction is when it arrives at the end of the axon, it triggers an opening of voltage gated Ca2+ channels in the axon terminals.
• 4) Release of neurotransmitter is when synaptic vesicles release ACh into synaptic cleft.
• 5) Binding of ACh diffuses across synaptic cleft.
• 6) Depolarisation of muscle fibre is binding ACh to receptors on the motor plate triggers an opening of channels, allowing influx of sodium (Na+) ions.
• 7) Muscle Contraction

  8) Terminal of Signal
• Involuntary control has two divisions, sympathetic and parasympathetic.
• 4 types of effectors

  1. smooth muscle
  2. cardiac muscle
  3. glands
  4. adipose (fat) tissue
• Neuron 1 contains cell body in brain and axon in the brain or spinal cord.
• Neuron 2 contains cell body in brain or spinal cord and the axon in PNS
• Neuron 3 contains cell body and axon in PNS
• Label Neuron 2 and Neuron 3

  A) Neuron 2

  B) pre-ganglionic

  C) Autonomic Ganglion

  D) synapse

  E) neuron 3

  F) post-ganglionic

  G) effector

  
• In neuron 2, the cell body in CNS, the axon extends in PNS, it is myelinated, the synapse is in autonomic ganglion and has a pre-ganglionic.
• In neuron 3, the cell body is in PNS, autonomic ganglion. Axon extends in PNS, to effector organ, it is unmyelinated. Synapse on effector organ and post-ganglion neuron.
• Neuron 2 neurotransmitter is acetylcholine (ACh)
• Neuron 3 neurotransmitter is ACh or norepinephrine.
• Autonomic nervous system has 2 divisions, sympathetic and parasympathetic. They both work together to maintain balance in autonomic system.
• Sympathetic division prepares body for stress responses. it has a fight or flight system and the effectors include: increased heart rate, constricting blood vessels to skin and viscera, gastric motility, salivation, pupil size and sweating.
• Parasympathetic division prepares the body for restful situations. It has a rest and digest system. The effectors included: decreased heart rate, gastric motility, pupil size and salivation.
• Sympathetic nervous system

  A) CNS

  B) ganglia

  C) thoracolumbar

  D) spinal cord

  E) short

  F) axon terminals

  G) synapse

  H) sympathetic ganglion

  I) sympathetic

  J) ganglion

  K) long

  
• Sympathetic chain is on either side of vertebral column and has 21-23 pairs. It is the place where preganglionic axons synapse onto postganglion input zone.
• Parasympathetic nervous system:

  A) cranial

  B) brainstem

  C) sacral

  D) spinal cord

  E) long

  F) parasympathetic ganglia

  G) parasympathetic ganglia

  H) short