What holds oxygen in muscles cells?

• Myofibrils

• Myoglobin

• Fascicles

• Periosteum

Muscles become fatigued by which of the following? (Select 4)

• Intense exercise

• Lack of ATP

• Too much lactate

• Oxygen debt

• Anaerobic respiration

The attachment of the tendon to the more stationary bone is called the _______.

• origin

• attachment
• extraction
• insertion

The attachment of the tendon to the more movable bone is called the _______.

• origin

• attachment
• extraction
• insertion

Which (2) of the following block the binding sites on actin filaments? ​ ​ ​ ​

• troponin

• tropomyosin

• z-lines

• calcium

• myosin

How much ATP is used in each myosin/actin cross-bridge cycle?

• 1

• 2

• 3

• 4

What causes your muscles to burn during a workout?

• lack of calcium

• lack of oxygen

• lack of water

• lack of acetylcholine

When myosin heads make a cross bridge and bend pulling the actin myofilament toward the center of the sarcomere, it is called the __.

• power stroke

• return stroke

• neuromuscular junction

• ATP contraction

Reorder the following in the order that they occur at the neuromuscular junction.

• Action potential arrives at the neuromuscular junction

• Acetylcholine binds to ligand (chemical) gated sodium channels

• Acetylcholine is released into the synaptic cleft

• Action potential is propagated in the sarcolemma

Reorder the following in the order that the events happen during contraction

• Myosin cross-bridges bind to the actin

• Myosin head binds an ATP molecule and detaches from the actin

• Free myosin head splits ATP

• Myosin head pivots toward the center of the sarcomere

• Calcium is released from sarcoplasmic reticulum and binds to troponin