9. PERIPHERAL NERVOUS SYSTEM (PNS)

• What is the peripheral nervous system comprised of?

  Nerves and ganglia
• What is the primary function of the peripheral nervous system?

  Connect limbs and organs to CNS
• How many systems is the peripheral nervous system divided into?

  Two systems
• What are the two systems of the peripheral nervous system?

  Sensory-somatic and autonomic nervous systems
• What types of nerves comprise the somatic nervous system?

  Cranial and spinal nerves
• How many pairs of cranial nerves are there?

  12 pairs
• Where do cranial nerves originate from?

  From the brain
• Which cranial nerves emerge from the cerebrum?

  First and second pairs
• What is the function of cranial nerves?

  Transmit sensory information and innervate muscles
• How many pairs of spinal nerves are there?

  31 pairs
• What do spinal nerves carry information between?

  Spinal cord and the body
• What is the difference between cranial and spinal nerves?

  Cranial nerves emerge from the brain
• What is the function of CN I (Olfactory nerve)?


  Sense of smell
• Where does CN II (Optic nerve) transmit information from?

  Retina of the eye
• What muscles does CN III (Oculomotor nerve) innervate?

  Eye muscles and iris
• What is the function of CN V (Trigeminal nerve)?

  Chewing and facial sensation
• What does the brachial plexus provide?

  Nerve supply to shoulders and upper limbs
• What is the location of the cervical plexus?

  Underneath the sternocleidomastoid muscle
• What does the phrenic nerve innervate?

  Top of the diaphragm
• What is the main function of the deep tendon reflex?

  Maintain balance
• What is a reflex?

  Involuntary movement in response to stimulus
• How does a reflex arc function?

  Includes sensory receptor, neuron, integrating center, motor neuron, effector
• What is neuropathy?

  Disease causing nerve function disturbance
• What is sciatica caused by?

  Irritation of the sciatic nerve
• What happens in carpal tunnel syndrome?

  Tendons in wrist become inflamed
• What is diabetic neuropathy associated with?

  Diabetes mellitus
• What does autonomic neuropathy affect?


  Internal body structures' functions
• What is postherpetic neuralgia?

  Pain after shingles infection
• What is the role of the integrating center in a reflex arc?

  Acts as a synapse between neurons
• How do nerve plexuses benefit limb muscles?

  Provide multiple nerve innervations for backup
• What is the function of CN IV (Trochlear nerve)?

  Movement of the eyeball
• What is the function of CN VI (Abducent nerve)?

  Movement of the eye
• What is the function of CN VII (Facial nerve)?

  Sensation of taste and facial expression
• What is the function of CN VIII (Auditory nerve)?

  Sense of hearing
• What is the function of CN IX (Glossopharyngeal nerve)?

  Taste sensation and saliva secretion
• What is the function of CN X (Vagus nerve)?

  Movement and secretion in organs
• What is the function of CN XI (Accessory nerve)?

  Movement of head and shoulders
• What is the function of CN XII (Hypoglossal nerve)?

  Movement of the tongue
• What are the segments of spinal nerves?

  C1-C8, T1-T12, L1-L5, S1-S5, coccygeal
• What are the types of spinal reflexes?

  Stretch, flexor, crossed extensor, superficial