Skeletal Muscles - exam practice

1, 2, and 3 are correct

only 1 and 2 are correct

only 2 and 3 are correct

only 1 is correct

attachment of the myosin head to actin

detachment of the myosin head from actin

return of the myosin head to the original (cocked) position

tilting of the myosin head

no change

shortens

lengthens

disappears

to form the Z-lines

to bind with calcium ions

to block the active sites on actin

to form cross-bridges with actin filaments

a type of muscle fibre

the functional unit of a myofibril

a protein that binds calcium

the cell-surface membrane of a muscle cell

a single globular protein

a fibrous protein with a tail and two bulbous structures at one end

a helical strand made of long threads

a molecule that blocks binding sites

it becomes wider

it remains the same width

it becomes narrower

it disappears completely

it is the site of ATP synthesis

it marks the boundary of a sarcomere

it is the location where myosin binds to actin

it stores calcium ions for muscle contraction

it forms the thin filaments

it binds calcium and helps position tropomyosin to expose binding sites on actin

it generates the action potential

it transports ATP to the myosin heads

it synthesises new protein filaments for muscle repair

it releases calcium ions to initiate contraction

it conducts the electrical signal along the muscle fibre

it stores ATP for muscle contractions