BackAs Luke fell off a ladder, he grabbed a tree branch with his right hand, but unfortunately lost his grip and fell heavily to the ground. Days later, Luke complained that his right upper limb was numb. What was damaged in his fall?
(a) Describe the formation and composition of a spinal nerve.
(b) Name the branches of a spinal nerve (other than the rami communicantes), and indicate their distribution.
Explain why you lose both motor and sensory function of a part of your body when a spinal nerve is numbed with anesthetic agents.
How does the strength of a sensory stimulus affect the generator potential in sensory receptors?
When Mr. Dinh goes to the emergency department with pain in the area along the midline of the diaphragm, he worries he is having a heart attack. Could the pain be related to his heart? Could it be related to any other organ(s)? Explain.
List the structural components of the peripheral nervous system, and describe the function of each component.
Label the following components of the corticospinal tracts with numbers 1 through 6, with 1 being the origin of the tracts and 6 their destination.
_____ Medullary pyramids where most fibers decussate.
_____ Anterior horn of the spinal gray matter.
_____ Midbrain and pons.
_____ Upper motor neurons in the primary motor and premotor cortices.
_____ Corona radiata and internal capsule.
_____ Lateral funiculus of the spinal cord.
Mr. Jake was admitted to the hospital with excruciating pain in his left shoulder and arm. He was found to have suffered a heart attack. Explain the phenomenon of referred pain as exhibited by Mr. Jake.
Mr. Frank, a former stroke victim who had made a remarkable recovery, suddenly began to have problems reading. He complained of seeing double and also had problems navigating steps. He was unable to move his left eye downward and laterally. Which cranial nerve was the site of lesion? (Right or left?)
Briefly describe the three stages of neuron development.
List and describe the basic steps involved in producing movement, beginning with the upper motor neurons in the cerebral cortex.