Well Answered 2026 Updated.
Characteristics of Muscles - Answer - Excitability
- Contractility
- Elasticity
- Extensibility
Functions of Muscle Tissue - Answer - Heat
- Movement
- Posture
Different Types of Muscle - Answer - Skeletal
- Smooth
- Cardiac
Differences Between Types of Muscle (Skeletal, Smooth, Cardiac) - Answer - Nuclei
- Striations
- Morphology
Organization of Skeletal Muscles - Answer Myofibril -> Myocyte -> Fascicle -> Skeletal Muscle
Skeletal Muscle Fiber Subtypes - Answer - Slow (Type 1) Oxidative
- Intermediate (Type IIa) Aerobic
- Fast (Type lib) Anaerobic
Myobrils are made up of: - Answer Sarcomeres
Sarcomere - Answer Unit of contraction
Contractile Element of the Sarcomere - Answer Myosin
Regulatory Elements of the Sarcomere - Answer Troponin and Tropomyosin
Function of Tropomyosin - Answer Blocks the myosin binding site
, What binds to TN-I? - Answer Actin
What binds to TN-T? - Answer Tropomyosin
What binds to TN-C? - Answer Ca2+
Actin assembly requires: - Answer ATP
What is Calcium's role in the sarcomere - Answer Ejects Tropomyosin and reveals the active
site
What are the two different kinds of actin? - Answer - G-actin: (globular-polymer)
- F-actin: (filamentous-polymer)
Steps of Power Stroke - Answer 1. ATP Binds to Myosin - Releases Actin (Rest state)
2. Myosin hydrolyzes ATP into ADP+Pi - Myosin head rotates and binds to actin
3. Power stroke (Pi) is released - Moves actin towards the M line
4. ADP is released - Myosin and actin stay bound
Molecular Basis of Contraction - Answer 1. Ca2+ levels increase in cytosol
2. Ca2+ binds to troponin
3. Troponin-C (Ca2+) pulls tropomyosin away from active site
4. Myosin binds to actin and completes power stroke
5. Actin filament moves towards the M line, completing the muscle contraction
NMJ (Neuromuscular Junction) - Answer Region where the motor neuron comes into close
proximity with the muscle fiber
Motor Unit - Answer consists of a single neuron and the muscle fibers it innervates
- motor unit only controls a few muscle fibers in an entire muscle
All-or-None Law - Answer the principle that the strength by which a nerve or muscle fiber
responds to a stimulus is independent of the strength of the stimulus. If that stimulus exceeds
the threshold potential, the nerve or muscle fiber will give a complete response; otherwise,
there is no response.