Question | Answer |
In the neuromuscular junction, the end of the motor neuron is called the: | Axon Terminal |
In the neuromuscular junction, the membrane of the muscle fiber is called | Sarcolemma |
The sarcoplasmic reticulum of a muscle fiber contains. | Calcium ions |
Within a sarcomere, the contracting proteins are: | mysoin and actin |
During a state of polarization,___ ions are abundant outside the cell, and ____ ions are abundant inside the cell. | Sodium / potassium |
During a state of polarization, the sarcolemma has a ___ charge outside and a ___ charge inside. | positive / negative |
During DEPOLARIZATION, the sarcolemma has a ___ charge outside and a ___ charge inside. | negative / positive |
When repolarization takes place,is potassium indside or outside the cell? Is sodium inside
or outside the cell? | outside / inside |
DEPOLARIZATION of a muscle fiber is stimulated by | Acetylcholine |
In the sliding filament mechanism of a muscle contraction,the stimulus for contraction is | Acetylcholine |
In the sliding filament mechanism of a muscle contraction,the proteins that inhibit contractions are | troponin and tropomyosin |
In the sliding filament mechanism of a muscle contraction, the proteins that slide past each other as the muscle fiber shortens are | actin / myosin |
For relaxation of the muscle to occur,__inactivates acetylcholine and ___ ions returned to the sarcoplasmic reticulum. | Cholinesterase / calcium |
A layer of connective tissue covering each muscle fiber. | Endomysium |
The layer of connective tissue covering the whole muscle. | Epimysium |
The cell membrane of each muscle fiber. | Sarcolemma |
Layer of connective tissue that covers the fascicles within each muscle. | Perimysium |
What two things happen to stimulate muscle contractions? | release of acetylcholine at motor end plate and release of calcium from sarcoplasmic reticulum |
Which myofibril does calcium bind to after release from the sarcoplasmic reticulum | Tropin |
Myosin forms a crossbridge when it binds to actin and pulls the actin. True or False | True |
What is required to help release the myosin heads from the actin and get them back into a cocked position? | ATP is needed for the myosin head crossbridge to detach from actin and re-cock |