Nerve and Muscle Physiology
Physiology · Topic 3
Source: NMC CBME Curriculum 2024 · Volume I · Physiology · Topic 3 · combined PDF page 151
Practice questions
- In the frog nerve–muscle study, approximately how long did eugenol take to induce loss of reflexes?
- After eugenol exposure, a frog sciatic nerve–gastrocnemius preparation still contracts when stimulated, but a higher voltage is needed and peak isometric force is lower. Which interpretation best matches the reported findings?
- In isolated sciatic nerves exposed to eugenol, which pair of changes was reported?
- An isolated sciatic nerve exposed to eugenol shows reduced compound action potential amplitude and increased threshold. Which experimental step was reported to reverse these effects?
- A laboratory compares isolated frog nerves after short and prolonged eugenol exposure. Which expectation is consistent with the study?
- Which recording arrangement was used to assess the response of the frog nerve–muscle preparation in the eugenol study?
- What is the most defensible conclusion about using eugenol for classroom frog nerve–muscle experiments?
- Which pairing correctly describes bladder and urethral smooth-muscle states during the filling phase?
- During normal voiding, which coordinated smooth-muscle pattern is described for the bladder and urethra?
- A proposed lower urinary tract mechanism is described as a negative-feedback modulator that dampens detrusor and urethral contractions. Which regulator best fits?
- Which statement best captures the role of ryanodine receptors in the lower urinary tract review?
- An investigator records both myogenic and nerve-evoked contractions in detrusor and urethral smooth muscle. Which regulator is specifically described as dampening both types of contraction?
- A review proposes BK channels and RyRs as possible therapeutic targets for some lower urinary tract symptoms. Which conclusion is warranted?
- Following peripheral nerve injury, which set of muscle changes is described as part of denervation-induced sarcopenia?
- A review discussing denervation-associated muscle change identifies calcium dysregulation and aberrant AMPK/mTOR signaling as contributors. What qualification does it make about the overall mechanism?
- Which description of 4-aminopyridine matches the peripheral nerve injury review?
- Which pairing correctly matches clemastine with the mechanism discussed in the peripheral nerve injury review?
- Which group consists entirely of neurotrophic factors discussed as supporting neuromuscular-junction stability and axonal regrowth?
- The review lists FOXO, GSK-3β, STAT3, and TGF-β/Smad in relation to denervation-associated muscle change. What role is assigned to these pathways?
- A proposed strategy after peripheral nerve injury aims both to support nerve repair and to preserve denervated muscle. How does the review characterize this approach?
- In the review of peripheral nerve stiffness, which imaging method is described as enabling real-time quantitative assessment of tissue stiffness?
- Which pattern of peripheral nerve stiffness is reported in the SWE review?
- After an adductor canal block, a researcher observes reduced saphenous nerve stiffness on SWE. Which interpretation is most appropriate based on the review?
- Which is a proposed mechanism for reduced peripheral nerve stiffness after adductor canal block?
- Why is the adductor canal described as an attractive model for studying dynamic peripheral nerve biomechanics?
- An adductor canal block is discussed as useful for perioperative analgesia. Which additional functional feature is highlighted in the review?
- A clinician proposes using SWE stiffness alone to diagnose peripheral nerve injury after regional anesthesia. Which limitation most directly challenges this proposal?