PHYS 261 Midterm & Final Exam Review
| 2026/2027 Updates with complete
solutions - WCU.
PHYS261 Final Exam
Review
You will have 2 hours to complete this 76-question
exam over
Chapters 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 24 &
26
,Chapter 12-Muscle
Review-Muscle Physiology Chapter 12
Key Points on Muscle Contraction:
For contraction to occur, a rise in Ca2++ is needed which is released from the sarcoplasmic reticulum (SR).
“Calcium induced calcium release” means: Once calcium enters the muscle cell, it goes to the sarcoplasmic reticulum and
causes more calcium to be released.
Order of events: Acetylcholine binds to receptors on the muscle cells>net influx of sodium into muscle cell>transverse
tubules bring action potentials into the interior of the cell>Ca2++ is released from the sarcoplasmic reticulum.
• When a new molecule of ATP binds to mysoin head during the sliding filament theory, mysoin head immediately
releases actin.
• The hydrolysis of ATP causes myosin to immeately come back into it’s cocked position.
Smooth muscle-Once Ca binds calmodulin, this complex then activate myosin light chain kinase.
,Key Points on Muscle Contraction
• Excitation Contraction Order of Events: Action potential travels down
the T-tubules>Depolarization of dihydropyridine receptor>opening of
ryanodine receptor>cross bridge formation
• Smooth Muscle Order of Events: Calcium is released from the
SR>Calmodulin is actived>Myosin light chain kinase is actived>ATP is
converted into ADP and Pi
• Sliding filament theory order: Thick and thin filaments slide past
eachother>ATP binds myosin>actin and myosin separate>ATP is
rearranged into ADP and Pi
, Key Points on Power Stroke
• ATP binds to myosin immediately after the power stroke.
• Excitation Contraction Order of Events: Action potential travels down the T-
tubules>Depolarization of dihydropyridine receptor>opening of ryanodine
receptor>cross bridge formation
• Smooth Muscle Order of Events: Calcium is released from the SR>Calmodulin is
actived>Myosin light chain kinase is actived>ATP is converted into ADP and Pi
• Sliding filament theory order: Thick and thin filaments slide past eachother>ATP binds
myosin>actin and myosin separate>ATP is rearranged into ADP and Pi
| 2026/2027 Updates with complete
solutions - WCU.
PHYS261 Final Exam
Review
You will have 2 hours to complete this 76-question
exam over
Chapters 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 24 &
26
,Chapter 12-Muscle
Review-Muscle Physiology Chapter 12
Key Points on Muscle Contraction:
For contraction to occur, a rise in Ca2++ is needed which is released from the sarcoplasmic reticulum (SR).
“Calcium induced calcium release” means: Once calcium enters the muscle cell, it goes to the sarcoplasmic reticulum and
causes more calcium to be released.
Order of events: Acetylcholine binds to receptors on the muscle cells>net influx of sodium into muscle cell>transverse
tubules bring action potentials into the interior of the cell>Ca2++ is released from the sarcoplasmic reticulum.
• When a new molecule of ATP binds to mysoin head during the sliding filament theory, mysoin head immediately
releases actin.
• The hydrolysis of ATP causes myosin to immeately come back into it’s cocked position.
Smooth muscle-Once Ca binds calmodulin, this complex then activate myosin light chain kinase.
,Key Points on Muscle Contraction
• Excitation Contraction Order of Events: Action potential travels down
the T-tubules>Depolarization of dihydropyridine receptor>opening of
ryanodine receptor>cross bridge formation
• Smooth Muscle Order of Events: Calcium is released from the
SR>Calmodulin is actived>Myosin light chain kinase is actived>ATP is
converted into ADP and Pi
• Sliding filament theory order: Thick and thin filaments slide past
eachother>ATP binds myosin>actin and myosin separate>ATP is
rearranged into ADP and Pi
, Key Points on Power Stroke
• ATP binds to myosin immediately after the power stroke.
• Excitation Contraction Order of Events: Action potential travels down the T-
tubules>Depolarization of dihydropyridine receptor>opening of ryanodine
receptor>cross bridge formation
• Smooth Muscle Order of Events: Calcium is released from the SR>Calmodulin is
actived>Myosin light chain kinase is actived>ATP is converted into ADP and Pi
• Sliding filament theory order: Thick and thin filaments slide past eachother>ATP binds
myosin>actin and myosin separate>ATP is rearranged into ADP and Pi
