Muscle force and characteristics

List the different types of myosin expressed in muscle and rank them according to their contraction velocity (Slow to fast)

• IIx<IIa<I

• I<IIx<IIa

• IIa<IIx<I

• I<IIa<IIx

The binding sites for the cross-bridges are located on

• actin

• myosin

• troponin

When muscle contracts upon stimulation, calcium ions bind to __________, which exposes the binding sites for the myosin cross‐bridges to attach to.

• actin

• myosin

• troponin

ATP is required for muscles to contract. Which of the following statements is FALSE?

• ATP is used to get the cross‐bridges to bind to actin.

• ATP is used to get the myosin head to release actin

• ATP is used to get the troponin‐tropomyosin complex to expose the binding sites.

Which statement is false.

Muscle force is regulated by______

• the type of fiber recruited

• muscle size

• the number of motor units recruited

• Glycogen levels