Sliding Filament Theory

Myosin is the ...

• Thin Filament of a muscle fibre

• Segment of a muscle fibre

• A molecule that changes shape when bound with Calcium Ions

• Thick Filament of a muscle fibre

True or False: Cross-bridges is when a myosin head attaches to an actin during contraction

• True

• False

___are regulatory proteins that cover the myosin binding site on the actin.

• troponin-tropomyosin

• sarcomere

• sarcolemma

• sarcoplasmic reticulum

___slides inward during muscle contraction.

• actin

• myosin

What happens to the H zone and I Band during contraction?

• They grow in size

• They stay the same

• They shrink in size

Whats happens to the A band during contraction?

• It grows in size

• It stays the same

• It shrinks in size

Do the lengths of the thick and thin filaments change during contraction?

• Yes

• No

_________ carries the impulse deep into the myofibrils.

• T-Tubules

• Synapses

• Sarcoplasm

• Neurotransmitters

What binds to the Myosin Head to cause it to detach from the Actin?

• ATP

• ADP

• CNS

• ETC

True or False: Myosin-Heads act as a ATPase.

• True

• False