exam 1 practice questions

Question 1

A postsynaptic neuron has a resting membrane potential of -70mV. Eighteen neurons form axosomatic synapses on the postsynaptic neuron. Near the axon hillock, 15 of the neurons produce EPSPs of 2 mV
each, while the others produce ISPS of 3 m each. The threshold of excitation of the postsynaptic cell is -50 mV. Will the postsynaptic cell produce an action potential?

Answer 1

yes
15(2)=30
3(3)=9
30-9=21
21-70=-49

Question 2

Conscious sedation is the practice of inducing brief, but heavy sedation of a patient, for example, to reduce patient distress during uncomfortable procedures such as reducing a shoulder dislocation or electrical cardioversion. Many pharmacological agents are available for conscious sedation; one such agent is Ketamine. IV administration of Ketamine rapidly induces dissociative anesthesia, a trance-like state providing pain relief, sedation, and amnesia by interfering with neuronal communication. While axonal impulse propagation is unaffected, synaptic transmission of signals is inhibited by ketamine by virtue of its action on pre-synaptic neurons. Based on your understanding of the action potential and synaptic transmission, explain the most likely mechanism of action of ketamine (that is to say, which specific cellular component is acted upon by the medication?)

Answer 2

it will interfere with voltage gated Ca channels

Question 3

Dental and oral surgery practices employ several pharmacological agents to achieve local anesthesia, for example, Marcaine (generic: bupivacaine hydrochloride and epinephrine injection). Many of these medications are locally injected, for example at the upper second molar to achieve posterior superior alveolar
nerve block. In the case of Marcaine, the addition of vasoconstrictive epinephrine to the solution increases local retention of the anesthetic agent bupivacaine at the site of injection, thus achieving anesthesia lasting up to 4 - 8 hours. While downstream nociceptors (pain receptors) are capable of generating action potentials in
sensory nerves, axonal propagation of these action potentials is inhibited by bupivacaine. Based on your understanding of the action potential and synaptic transmission, explain the most likely mechanism of action of bupivacaine that is to say, which specific component of nerve cells is acted upon by the medication?

Question 4

A. Patient quickly and clearly states “apples, oranges, bananas, grapes…” when asked to name different types of fruit. Patient is then presented with a collage of different fruit clipart and is unable to identify which item is an apple.
B. Patient experiencing numbness and tingling in the legs.
C. Patient with no prior neurological deficits presenting with sudden onset, right-sided weakness. Patient’s right grip strength is notably weaker; when patient outstretches both arms then closes their eyes, the right arm drifts downward.
D. Patient has difficulty performing command to “touch your nose then then touch my index finger”; patient touched their cheek then missed your outstretched hand entirely. She reports dizziness, nausea, and the sensation that she is falling toward her left side.

Answer 4

a. vision, occipital lobe
b. middle
c. left brain
d. cerebellum

Question 5

A 23-year-old male sustained a back injury during a sporting event and subsequently experienced delayed but rapidly progressive neurological impairment. CT imaging and detailed neurological examination were preformed. A diagnosis of incomplete, right-sided SCI at the level of T4 is made. What neurologic deficits would the patient most likely present with

Answer 5

Contralateral: Loss of pain, temperature, and crude touch sensation
Ipsilateral: loss of vibration, body position, pressure, and discriminative touch sensation
Loss of motor function.

Question 6

A. Pt fell from 2nd story roof and experienced loss of consciousness for < 5 mins. Pt now speaking in full-sentences is describing sensory and motor function loss in all extremities.
B. Pt admitted to neuro unit after gunshot wound with spinal involvement. Patellar reflexes observed to be asymmetrical. Pt displays bilaterally intact creamstic reflexes. Left Achilles tendon reflex is normal while right-sided response is noted a s hyperreflexic.
C. Pt displays normal biceps and triceps tendon reflexes, bilaterally absent abdominal reflex, and bilaterally hyperreflexic patellar tendon reflexes.
D. Pt struck by vehicle while crossing street. Pt is able to breathe without support
but appears in distress. When assessing motor function, the provider notes
strong, equal grip strength bilaterally. Pt’s skin is flushed below the nipple line; HR is 45 bpm; BP is 64/44 mmHg.

Answer 6

a. level of C6, complete
b. level of L3 incomplete
c. level of T11 complete
d. level of T4 complete

Question 7

Pair each drug to a patient:
A. A 34-year old pregnant female has not received prenatal
care because she is uninsured. She presents in the ER with severe headache. She is diagnosed with acute hypertensive crisis resulting from pregnancy complications.
B. An 83-year old female with a 60+ year smoking history is admitted to the hospital for acute exacerbation of COPD and emphysema symptoms.
C. A 6-year old boy with a known peanut allergy was inadvertently exposed to food prepared with peanut oil. Within 5 minutes of exposure his face is notably swollen; his respirations are labored with audible wheezing.
D. A 64-year old female has a history of diabetes, heart disease, and hypertension. Her diabetes is well-managed by diet modification; her primary care nurse practitioner suggests a blood pressure medication to lower her risk of a heart attack or stroke.

1. Epinephrine
2. Albuterol (Beta-2 AR agonist)
3. Labetalol (Alpha-1 AR antagonist)
4. Metoprolol (Beta-1 AR antagonist)

Answer 7

1. C
2. B
3. A
4. D