Muscular System: Excitation-Contraction Coupling
1. What ion is stored in the terminal cisterns of the sarcoplasmic reticulum?
- Calcium
2. Where is actin found in the sarcomere?
- The region between two Z lines
3. Each subunit on actin contains binding sites for _______.
- Myosin head
4. What is the function of tropomyosin?
- Tropomyosin regulates the contraction in both muscles and non muscle cells and is
found in all animal cells.
5. An action potential can be triggered on the sarcolemma of a muscle fiber only after what
structure has been depolarized by a motor neuron?
- The motor endplate
6. Voltage-gated proteins embedded in which structure will cause the opening of calcium
channels in the terminal cisterns of the sarcoplasmic reticulum?
- T-TUBULES
7. A change in the shape of what protein causes tropomyosin to shift away from binding sites on
actin?
- Troponin
8. Which ion is the link between excitation and contraction in a skeletal muscle contraction?
- Sodium
1. What ion is stored in the terminal cisterns of the sarcoplasmic reticulum?
- Calcium
2. Where is actin found in the sarcomere?
- The region between two Z lines
3. Each subunit on actin contains binding sites for _______.
- Myosin head
4. What is the function of tropomyosin?
- Tropomyosin regulates the contraction in both muscles and non muscle cells and is
found in all animal cells.
5. An action potential can be triggered on the sarcolemma of a muscle fiber only after what
structure has been depolarized by a motor neuron?
- The motor endplate
6. Voltage-gated proteins embedded in which structure will cause the opening of calcium
channels in the terminal cisterns of the sarcoplasmic reticulum?
- T-TUBULES
7. A change in the shape of what protein causes tropomyosin to shift away from binding sites on
actin?
- Troponin
8. Which ion is the link between excitation and contraction in a skeletal muscle contraction?
- Sodium
