ATI RN
Questions About the Muscular System Questions
Question 1 of 5
The tibialis anterior is named according to
Correct Answer: D
Rationale: The tibialis anterior's name reflects its location anterior (front) of the tibia in the lower leg. Muscle names often denote position, here indicating its role in dorsiflexing the foot from the shin's front. Size (e.g., maximus) or shape (e.g., deltoid) apply elsewhere, not here. Fiber direction (e.g., oblique) isn't the focus location is. This positional naming distinguishes it, aligning with anatomical convention for identifying muscle placement and function.
Question 2 of 5
Identify the group of muscles on the anterior thigh.
Correct Answer: D
Rationale: The quadriceps group rectus femoris, vastus muscles lies on the anterior thigh, extending the knee and flexing the hip, as in kicking. Abductors are lateral, adductors medial, hamstrings posterior. Quadriceps' anterior placement and extension role distinguish them, vital for leg straightening, unlike positional or opposing groups.
Question 3 of 5
In the process of muscle contraction, what happens when ATP binds to the myosin head?
Correct Answer: C
Rationale: During muscle contraction, the cross-bridge cycle drives filament sliding. After myosin binds to actin and performs a power stroke pulling actin toward the sarcomere's center ATP binds to the myosin head. This binding reduces myosin's affinity for actin, breaking the cross-bridge and detaching myosin, allowing it to reset for another cycle. ATP is then hydrolyzed to ADP and phosphate, cocking the head into a high-energy state to reattach to actin. Calcium ions, managed by the sarcoplasmic reticulum, regulate actin exposure, not myosin detachment. Acetylcholine release occurs at the neuromuscular junction, unrelated to ATP's role here. Hydrolysis energizes myosin but doesn't cause attachment binding does the detachment. This ATP-driven detachment is critical for repeated contractions, distinguishing it from initiation or calcium-related steps, and underscores its mechanical role in muscle dynamics.
Question 4 of 5
The bones that participate in the formation of the anterior cranial fossa are all the following, EXCEPT:
Correct Answer: C
Rationale: The anterior cranial fossa, housing the frontal brain lobes, is formed by the orbital part of the frontal bone (roof), ethmoid bone (midline, cribriform plate), and sphenoid bone (lesser wings, posteriorly). These create a shallow depression. The temporal bone, lateral and forming the middle fossa, doesn't contribute anteriorly its squamous and petrous parts support the temporal lobes instead. The frontal bone's orbital plate, ethmoid's midline, and sphenoid's wings align with the fossa's anatomy, while the temporal's exclusion reflects its distinct cranial position, critical for understanding skull compartmentalization.
Question 5 of 5
Endurance type exercise training modulates fuel storage and substrate use. Adaptive responses include:
Correct Answer: D
Rationale: Endurance training enhances intramuscular lipid use during exercise, increasing storage and oxidation efficiency as mitochondria and enzymes adapt, sparing glycogen for longer efforts. Lowering intramuscular lipid storage contradicts this training boosts it for fuel. Increasing liver glycogen content occurs, but it's not the primary exercise-use adaptation; it supports glucose homeostasis. Increasing muscle glycogen use during exercise opposes training's glycogen-sparing effect use efficiency improves, not quantity. Intramuscular lipid reliance grows, distinguishing it as a key adaptation, aligning with endurance's fat-burning shift, unlike glycogen-focused or storage-reducing changes.