Nokea
As the action potential swings down,
- A. potassium ions move out of the axon.
- B. potassium ions move into the axon.
- C. sodium ions move into the axon.
Correct Answer: A
Rationale: During the repolarization phase of an action potential, potassium ions move out of the axon, restoring the negative charge inside the neuron. This efflux of potassium ions helps return the membrane potential to its resting state after depolarization. The movement of potassium ions is facilitated by voltage-gated potassium channels, which open in response to the change in membrane potential.
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In assessing Bob, which of the following complaints would indicate radial nerve injury?
- A. Pain at the fracture site
- B. Inability to extend the wrist
- C. Inability to flex the elbow
- D. Paralysis of the hand and forearm
Correct Answer: B
Rationale: The radial nerve primarily controls wrist extension; inability to extend the wrist indicates radial nerve damage.
Priority Decision: A patient has fallen in the bathroom of the hospital room and reports pain in the upper right arm and elbow. Before splinting the injury, the nurse knows that the priority management of a possible fracture should include which action?
- A. Elevation of the arm
- B. Application of ice to the site
- C. Notification of the health care provider
- D. Neurovascular checks below the site of the injury
Correct Answer: D
Rationale: Neurovascular checks ensure no compromise to blood supply or nerve function.
The client is having a lumbar puncture performed. The nurse would plan to place the client in which position for the procedure?
- A. Side-lying, with legs pulled up and head bent down onto the chest
- B. Side-lying, with a pillow under the hip
- C. Prone, in a slight Trendelenburg's position
- D. Prone, with a pillow under the abdomen
Correct Answer: A
Rationale: The side-lying position with legs pulled up and head bent down onto the chest is the standard position for a lumbar puncture. This position maximizes the space between the vertebrae, allowing easier access to the subarachnoid space for cerebrospinal fluid (CSF) collection. Proper positioning is critical to ensure the procedure is performed safely and effectively.
What is different when a lesion occurs in a lower motor neuron compared to in an upper motor neuron?
- A. Causes hyporeflexia and flaccidity
- B. Affects motor control of the lower body
- C. Arises in structures above the spinal cord
- D. Interferes with reflex arcs in the spinal cord
Correct Answer: A
Rationale: Lower motor neuron lesions typically result in hyporeflexia and flaccidity due to direct involvement of motor neurons.
Bilateral affection of spinal cord at the cervical level may produce the following syndrome:
- A. hemiplegia
- B. paraplegia
- C. tetraplegia
- D. monoplegia
Correct Answer: C
Rationale: Tetraplegia is the correct answer because damage to the cervical spinal cord affects both the upper and lower limbs, resulting in paralysis of all four extremities. This condition occurs due to the disruption of motor and sensory pathways at the cervical level, which control limb function.