ATI RN
Multiple Choice Questions on Muscular System Questions
Question 1 of 5
The connective tissue covering of a fascicle is known as
Correct Answer: B
Rationale: Muscle tissue is organized hierarchically, with fascicles bundles of muscle fibers encased by perimysium, a connective tissue sheath. This layer provides structural support, houses blood vessels and nerves, and separates fascicles within the muscle, facilitating coordinated contraction. Endomysium surrounds individual muscle fibers, a finer layer penetrating within fascicles. Epimysium envelops the entire muscle, integrating with tendons dense connective tissue linking muscle to bone. Deep fascia, a broader sheet, encases muscle groups externally, not specific fascicles. The perimysium's role is critical: its collagen and elastin composition balances flexibility and strength, protecting fascicles during stretching or contraction. Histological analysis reveals its thicker, more organized structure compared to endomysium's reticular fibers, distinguishing it from tendons' load-bearing function or epimysium's holistic coverage. Misidentifying these layers could obscure muscle organization, but perimysium's fascicle-specific wrapping is evident in dissections and biomechanical studies, underscoring its intermediate position in muscle anatomy.
Question 2 of 5
The physician has prescribed isometric exercises for a patient. The patient asks the nurse how these exercises work. The nurse uses an example to explain the physiology of isometric exercises, which is:
Correct Answer: A
Rationale: Isometric exercises involve muscle contraction without joint movement, building strength by maintaining tension against resistance. Flexing the lower arm while resisting with the other hand exemplifies this: the biceps contract but the elbow angle stays fixed, engaging muscle fibers statically. Pulling knees to the chest involves dynamic movement, not isometric principles. Forcefully flexing the neck to touch the chin implies motion, not static tension. Flexing toes upward while lying flat also involves joint movement, missing the isometric focus. The arm example clearly demonstrates how muscles work against an opposing force without changing position, aligning with the physiology of isometric training to enhance strength in a targeted, controlled way.
Question 3 of 5
The nurse is changing the position of a person with flaccid paralysis. The priority action will be:
Correct Answer: A
Rationale: Flaccid paralysis causes muscle limpness, increasing the risk of joint stiffness or deformity from prolonged immobility. Changing joint position is the priority to prevent contractures and maintain alignment, using careful support to avoid strain. Not using a footboard might prevent footdrop in some cases, but it's secondary to overall joint care. Moving only side to side limits flexibility and risks pressure sores, ignoring full-body needs. Avoiding pillows dismisses a tool for support, which isn't the issue positioning is. Adjusting joints takes precedence, as it directly addresses the paralysis-related risk of fixed postures, ensuring long-term mobility and comfort.
Question 4 of 5
The industrial nurse examines an employee who states that his right shoulder hurts when he abducts it and points with one finger to the spot at the point of his shoulder that is painful. He mentions that he won a racquetball tournament yesterday. The nurse suspects the employee is suffering from:
Correct Answer: B
Rationale: Pain on shoulder abduction, localized to the point of the shoulder after intense activity like racquetball, suggests bursitis inflammation of the subacromial bursa from overuse. This bursa cushions the rotator cuff, and repetitive overhead motions can irritate it, causing sharp pain during movement. A rotator cuff tear would likely limit strength and range more severely. Dislocation involves joint displacement, with visible deformity and acute trauma, not just post-game pain. Subluxation is partial dislocation, also unlikely without instability signs. Bursitis fits the acute, activity-triggered presentation, making it the nurse's likely suspicion, treatable with rest and anti-inflammatories.
Question 5 of 5
The region of the pelvic floor inferior to the pubic symphysis, bounded by the pubic symphysis and the ischial tuberosities, and containing the external genitalia.
Correct Answer: C
Rationale: The pelvic floor is divided into two main regions: the anal triangle and the urogenital triangle. The description provided inferior to the pubic symphysis, bounded by the pubic symphysis and ischial tuberosities, and containing the external genitalia specifically refers to the urogenital triangle. This region is located anteriorly in the perineum and includes structures such as the urethra and external genitalia in both males and females. The term deep is a directional descriptor and does not define a specific region. Fixators refers to muscles that stabilize the origin of a prime mover, unrelated to pelvic floor anatomy. Superficial is another directional term and does not match the detailed anatomical boundaries provided. Thus, urogenital triangle is the correct answer, as it precisely corresponds to the anatomical area described in the question, distinguishing it from other regions like the anal triangle.