Musculoskeletal System Review

Heat released from contracting muscles functions to __________.

• maintain posture

• maintain body temperature

• store nutrient reserves

• support soft tissues

The perimysium surrounds a bundle of muscle fibers called a __________.

• thick filament

• tendon

• fascicle

• sarcomere

Which connective tissue layer wraps the entire muscle?

• perimysium

• endomysium

• epimysium

• aponeurosis

Which structure in a muscle fiber or muscle cell is continuous with the sarcolemma and carries the signal to contract deep into the muscle cells?

• sarcoplasm

• myofibrils

• sarcoplasmic reticulum

• T tubules

The repeating functional units seen on the myofibrils are __________.

• sarcomeres

• terminal cisternae

• thin filaments

• T tubules

Which of the following is NOT found in a thin filament?

• tropomyosin

• actin

• troponin

• myosin

The neurotransmitter required to trigger skeletal muscle contraction is __________.

• calcium

• myosin

• acetylcholine (ACh)

• adenosine triphosphate (ATP)

What must bind to troponin in order to expose the active sites on actin?

• calcium ions

• myosin

• acetylcholine

• ATP

What is the type of contraction in which the muscle does NOT change length and the contraction does NOT produce tension that exceeds the load?

• concentric

• isotonic

• tetanus

• isometric

What is the name of the structure that contains gap junctions and desmosomes and joins the plasma membranes of two cardiac muscle cells together?

• intercalated discs

• T tubules

• dense bodies

• sarcoplasmic reticulum