ATI RN
Multiple Choice Questions Muscular System Questions
Question 1 of 5
Which of the following statements is correct about what happens during flexion?
Correct Answer: B
Rationale: Flexion decreases the angle between bones, as when bending the elbow (humerus and radius/ulna angle shrinks), a fundamental joint movement in kinesiology. Increasing the angle describes extension, not flexion. Moving away from the body aligns with abduction, not flexion, which typically occurs in a sagittal plane. Moving toward the body's center might suggest adduction, but flexion is about angle reduction, not midline proximity (e.g., knee flexion doesn't necessarily approach the midline). The angle decrease precisely defines flexion's action, making it correct.
Question 2 of 5
The large muscle group that attaches the leg to the pelvic girdle and produces extension of the hip joint is the group.
Correct Answer: A
Rationale: The gluteal group (gluteus maximus, medius, minimus) attaches the femur to the pelvic girdle, with gluteus maximus primarily extending the hip (e.g., standing from sitting). Obturator muscles rotate the thigh, not extend. Adductors pull the leg inward. Abductors move it outward (e.g., gluteus medius), not extend. Gluteals' size and hip extension role, per lower limb mechanics, make 'a' the correct group.
Question 3 of 5
The temporalis muscle, which helps close the jaw, attaches to the which part of the mandible?
Correct Answer: C
Rationale: The temporalis muscle, originating from the temporal fossa, inserts on the mandible's coronoid process, a sharp, anterior projection, elevating the jaw for chewing. 'Turbulance' is a typo or nonsense term, not anatomical. Mandibular condyles articulate with the skull at the TMJ, not the temporalis insertion. Conchae , nasal structures, are unrelated to the mandible. The coronoid process's role as the temporalis's anchor, enhancing bite force, makes 'c' the correct attachment point.
Question 4 of 5
Which part of the tibia is known as 'ankle bone'?
Correct Answer: C
Rationale: The medial malleolus, the tibia's distal medial projection, is known as the 'ankle bone,' forming the inner ankle bulge, articulating with the talus for stability. Tibial tuberosity is a proximal knee landmark. Anterior crest is the shin's ridge. Fibular notch connects to the fibula, not the ankle joint. The medial malleolus's prominence and ankle role, per lower leg anatomy, make 'c' correct.
Question 5 of 5
What is the largest part of the human brain?
Correct Answer: C
Rationale: The cerebrum, occupying the upper cranial cavity, is the human brain's largest part, comprising about 80% of its mass. Located above the brainstem and cerebellum, it handles higher functions thinking, memory, and voluntary movement via its cerebral cortex, divided into four lobes: frontal (problem-solving), parietal (sensation), temporal (auditory processing), and occipital (vision). Its size and convoluted surface, with gyri and sulci, maximize neuron density, supporting complex cognition unique to humans. The midbrain, a small brainstem segment, relays sensory and motor signals but is far smaller. The medulla oblongata, also brainstem, regulates vital functions like breathing but is compact. The cerebellum, below the cerebrum, coordinates movement and balance, yet its volume is less than the cerebrum's. Neuroanatomy studies quantify the cerebrum's dominance around 1,300-1,400 grams in adults dwarfing other regions, underscoring its evolutionary expansion for intelligence and adaptability, distinct from smaller, specialized structures.