ATI RN
Questions About the Skeletal System Questions
Question 1 of 5
What are the two main divisions of the skeletal system?
Correct Answer: A
Rationale: The skeletal system is divided into the axial skeleton (skull, vertebral column, thoracic cage; 80 bones) and the appendicular skeleton (limbs, girdles; 126 bones), totaling 206 bones in adults. B refers to bone shapes, C to bone tissue types, and D to joint/connective tissue types—none are the main divisions.
Question 2 of 5
Which division of the skeletal system includes bones of the skull, vertebral column, and rib cage?
Correct Answer: A
Rationale: The skeletal system is divided into two main parts: the axial skeleton and the appendicular skeleton. The axial skeleton includes the bones that form the central axis of the body, such as the skull (which protects the brain), the vertebral column (which protects the spinal cord), and the rib cage (which protects the heart and lungs). The appendicular skeleton, in contrast, includes the limbs and girdles. Long bones and irregular bones are types of bones, not divisions of the skeletal system, making 'Axial skeleton' the correct choice.
Question 3 of 5
What is the neurotransmitter responsible for transmitting signals from motor neurons to muscle fibers at the neuromuscular junction?
Correct Answer: B
Rationale: At the neuromuscular junction, motor neurons release acetylcholine (ACh) into the synaptic cleft to stimulate muscle fiber contraction. ACh binds to receptors on the muscle cell membrane, triggering an action potential that leads to contraction. Dopamine, serotonin, and GABA are neurotransmitters involved in other neural functions, not muscle contraction, making 'Acetylcholine (ACh)' the correct answer.
Question 4 of 5
Which protein, found in muscle fibers, slides along actin filaments during muscle contraction to generate force?
Correct Answer: A
Rationale: During muscle contraction, the sliding filament theory explains that myosin filaments slide along actin filaments to shorten the sarcomere and generate force. Myosin heads bind to actin, pulling it inward. Troponin and tropomyosin regulate this process, while collagen is structural, not contractile, making 'Myosin' the correct answer.
Question 5 of 5
The bones of the appendicular skeleton are involved in:
Correct Answer: B
Rationale: The appendicular skeleton, including limbs and girdles, is designed for movement and locomotion. Bones like the femur and humerus enable walking and arm motion, supported by the pelvic and pectoral girdles. Protection of organs is an axial skeleton role, making 'Facilitating movement and locomotion' the correct answer.