Reflex Arc Lab

Question 1

What is a reflex?

Answer 1

-simple motor response made without the involvement of large numbers of interneurons

Question 2

Which reflexes (done in lab) require only one synapse between the sensory and motor neurons

Answer 2

• monosynaptic stretch reflexes
  
  • knee jerk (tests femoral nerve)
  • ankle jerk reflex ( tests medial popliteal nerve)
  • biceps jerk reflex (tests musculocutaneous nerve)
  • triceps jerk reflex (tests radial nerve)
  • patellar reflex

Question 3

Explain how a crossed extensor reflex is “complicated”

Answer 3

• The sensory impulses may travel longitudinally and transversely within the gray matter, stimulating other motor neurons
  
  • this may lean to the contraction of other flexor muscles on the same side and or opposite side, while inhibiting the contraction of antagonistic muscles

Question 4

What are muscle spindles?

Answer 4

-distinctive stretch receptors witching the connective tissue of the muscle, and consists of specialized thin muscle fibers (intrafusal fibers) innervated by sensory neurons