Tamara's muscle weakness and fatigue becomes progressively worse over the course of the day. this is a hallmark sign of myasthenia gravis, an autoimmune disorder that affects the ability of a motor neuron to communicate with a muscle fiber. what synaptic events must happen first for excitation to occur?

a. the action potential travels down the t tubules in the sarcolemma and triggers the release of calcium ions from the sarcoplasmic reticulum.
b. calcium binds to tropomyosin, shifting it from the active site on actin, allowing cross bridge formation to occur as myosin binds to the active site.
c. acetylcholine is released from the axon terminal and diffuses across the synapse to bind to a receptor in the surface of the motor end plate.
d. sodium ions from the extracellular fluid diffuse into the cytosol of the muscle fiber, triggering the generation of an action potential in the sarcolemma.

Rita schmidt, 74 years of age, is a female patient who was admitted to the surgical unit after undergoing removal of a section of the colon for colorectal cancer. the patient does not have a colostomy. the patient has several small abdominal incisions and a clear dressing over each site. the incisions are well approximated and the staples are dry and intact. there is a jackson-pratt drain intact with minimal serous sanguineous drainage present. the patient has a salem sump tube connected to low continuous wall suction that is draining a small amount of brown liquid. the patient has no bowel sounds. the foley catheter has a small amount of dark amber-colored urine without sediments. the patient has sequential compression device (scd) in place. the nurse performs an assessment and that the patient's breath sounds are decreased bilaterally in the bases and the patient has inspiratory crackles. the patient's cardiac assessment is within normal limits. the patient is receiving o2 at 2 l per nasal hg; heart rate 110 bpm; respiratory rate 16 breaths/min; and the patient is afebrile. the patient is confused as to place and time. cannula with a pulse oximetry reading of 95%. the vital signs include: blood pressure, 100/50 mm. a. explain the assessment parameters used to provide clues to detect postoperative problems early and the interventions needed. b. what gerontological postoperative considerations should the nurse make?