Movement Neuroscience 1

What is the basic structural and contractile unit of a muscle fiber?

• Myofibril

• sarcomere

• myoglobin

• endomysium

According to the sliding filament theory, which proteins slide past each other during muscle contraction?

• Actin and Myosin

• Troponin and Tropomyosin

• Myoglobin and Myosin

• Sarcomere and Sarcoplasm

What is the term for the force generated by a contracting muscle?

• Elasticity

• Tension

• Isometric

• Relaxation

In a sarcomere, what happens to the length of the H-zone during muscle contraction?

• It shortens

• It disappears

• It lengthens

• It remains constant

During muscle contraction, what is the role of myosin heads?

• Anchor the sarcomere

• Bind to actin and form cross-bridges

• Inhibit tropomyosin movement

• Store calcium ions

What structure anchors the thin filaments in a sarcomere?

• • H-zone

• Z-disk

• M-line

• A-band

What triggers the movement of tropomyosin, exposing the binding sites on actin?

• Calcium ions

• ATP

• Myoglobin

• Creatine phosphate

What happens to tension development when a muscle fiber is stretched beyond its optimal length?

• Tension increases

• Tension decreases

• Tension remains constant

• Tension becomes isometric

What is the primary energy source for muscle contraction at the molecular level?

• Glucose

• ATP

• Oxygen

• Lactic acid

What is responsible for the force generated during active muscle contraction?

• Passive tension

• Myosin cross-bridges

• Elastic recoil

• Sarcomere length